Welcome to yet another issue of (IN)SECURE. The book contest we held in the previous issue was a great
success and here are the winners: Dominic White, Dr. Gary Hinson, Ronaldo Vasconcellos, Joey Ortiz,
Adrian St. Onge and Frantisek Holop.
To all of you that sent us insightful comments we thank you, (IN)SECURE will grow to be better because of
it. Expect more contests in the future and keep that feedback running, there’s always place for us to im-
prove. If you’re interested in writing for (IN)SECURE feel free to contact us, we take a look at all submis-
sions and ideas.
Enjoy the magazine!
Mirko Zorz
Chief Editor
Visit the magazine website at www.insecuremag.com
(IN)SECURE Magazine contacts
Feedback and contributions: Mirko Zorz, Chief Editor – editor@insecuremag.com
Advertising and marketing: Berislav Kucan, Director of Marketing – marketing@insecuremag.com
Distribution
(IN)SECURE Magazine can be freely distributed in the form of the original, non modified PDF document.
Distribution of substantively modified versions of (IN)SECURE Magazine content is prohibited without the
explicit permission from the editor. For reprinting information please send an email to
reprint@insecuremag.com or send a fax to 1–866–420–2598.
Copyright HNS Consulting Ltd. 2005.
www.insecuremag.com 3
Secure Mobile Access Solution for PDAs and Smart Phones
Aventail announced Aventail Mobile, the market’s most complete
SSL VPN for mobile devices, providing easy access to critical ap-
plications from virtually any mobile device with complete security
and granular access control. Aventail Mobile supports all major
operating systems, including Blackberry, Palm, Windows Mobile,
DoCoMo, and Symbian.
The Aventail Secure Mobile Access Solution will be available in Q4 2005. WorkPlace Mobile will be in-
cluded in the overall Aventail Smart SSL VPN platform. Connect Mobile is an add-on feature priced from
$995.00.
(ISC)2 Information Security Scholarship For 2006
The International Information Systems Security Certification Consortium, Inc. announced it is
accepting applications for the Annual (ISC) 2 Security Scholarship Program for 2006, which
offers $50,000 in financial assistance to post-graduate students who are conducting informa-
tion security research projects.
One-year scholarships of up to $12,500 apiece will be awarded to four qualifying full-time post-graduate
students pursuing an advanced degree in information security at any accredited university worldwide. The
scholarships may be consecutively renewed if all criteria have been met, or for multiple research projects.
The deadline for submission is Nov. 30, 2005.
To obtain the (ISC) 2 Information Security Scholarship form, prospective candidates should go to
www.isc2.org/scholarship.
Symantec Completes Acquisition of WholeSecurity
Symantec Corp. announced the completion of its acquisition of WholeSe-
curity, Inc., a leading provider of behavior-based security and anti-phishing
technology. WholeSecurity solutions protect PCs from threats such as
worms, Trojan horses, keystroke loggers, and phishing attacks. WholeSe-
curity’s products leverage behavioral technology to protect users from
these threats, whether they are known or unknown, on both managed and
unmanaged PCs. The acquisition was announced on Sept. 22, 2005.
www.insecuremag.com 4
Survey Shows that Companies Don’t Secure Data “On the Move”
Senforce Technologies Inc. announced the findings of research it
conducted by surveying 56 public and private sector organizations.
The Senforce survey revealed that while 87 percent of critical
business data is found on endpoint PCs, 56 percent of those asked
think their current wireless network security strategy is reactive or
inadequate. Other key survey findings include:
- 82 percent of new PC procurements are notebooks versus desktop PCs.
- 74 percent of those notebooks are wireless-enabled.
- 92 percent are concerned about notebooks moving in and out of the network perimeter.
- 43 percent have deployed production wireless networking infrastructure with defined policies.
- 63 percent prefer non-proprietary wireless networking hardware solutions.
F-Secure Mobile Anti-Virus Extended to Cover Windows Mobile OS
F-Secure Corporation announced that it is to extend the support for its award-winning F-
Secure Mobile Anti-Virus to Microsoft’s Windows Mobile operating system. The solution
brings new levels of protection for Windows Mobile users.
F-Secure Mobile Anti-Virus and F-Secure Mobile Security can be purchased from se-
lected mobile operators or directly from the F-Secure eStore at:
http://www.f-secure.com/estore/. A free 30-day trial is also available in the mobile-device
optimized F-Secure Mobile Portal: mobile.f-secure.com.
Study Reveals Spyware Encounters are Increasing at Work
Trend Micro, Inc. announced key findings from a study that reveals that more
than 87 percent of corporate end users are aware of spyware, and yet 53 per-
cent of survey respondents demand greater education from IT to better under-
stand the threat. The findings indicate that awareness does not translate to
knowledge, and as a result users are looking to their IT departments to play a
more protective role. Some of the findings include:
- Viruses and Spyware are perceived as being more serious threats to corporate security than spam.
- 26% American SMB workers, and 21% American enterprise workers stated that they had fallen victim to
spyware while at work.
- Among U.S. based respondents, the top five consequences of being victimized by spyware were lower
computer performance, malicious downloads, violation of privacy and more.
Funk Software Ships Endpoint Integrity Solution Based On TCG’s Trusted Network !
Connect Standards
Funk Software announced general availability of its suite of endpoint integrity products, in-
cluding new Steel-Belted Radius/Endpoint Assurance and a new version of its secure, low-
overhead 802.1X supplicant Odyssey Client.
The client lets enterprises take a proactive approach to network security and significantly
strengthen the protection of their networks – using a standards-based approach that permits
interoperability across a wide variety of vendor offerings and ensures scalability to future
technologies.
www.insecuremag.com 5
One day while working on the latest security problem, a member of the net-
work administration team walks toward your desk carrying a CD-ROM. She
drops the disc in front of you and asks “Would you mind looking at this traf-
fic? Joe thinks there might be a security incident here.”
You respond by casually slipping the CD-ROM into STA consists of the following steps. The process
your laptop, responding “No problem! I’ll get right assumes you are an analyst supporting a client,
on that.” As the network administrator walks away, although the methodology applies to traffic you
you load the 2 GB trace file into Ethereal. After collect yourself. The four forms of NSM data – sta-
listening to your hard drive groan and thrash, you tistical, session, full content, and alert – each play
eventually see millions of packets staring at you. a role.
You stare back and wonder “Now what?”
1. Make a new directory on the analysis platform
If this scenario sounds familiar, you are not alone. specifically for the investigation at hand.
Thousands of network analysts around the world 2. Copy the trace into the analysis directory and
think packet analysis begins and ends with Ethe- change the trace permissions to read-only.
real. The open source protocol analyzer is indeed 3. Hash the trace and copy the hash elsewhere.
an excellent tool, but it isn’t necessarily the pro- 4. (optional) Run Capinfos on the trace to acquire
gram with which one should begin a network in- initial statistical data.
vestigation. This is especially the case when per- 5. Run Tcpdstat on the trace to obtain basic statis-
forming a zero-knowledge assessment, where the tical data.
analyst is given little or no information regarding 6. Run Argus on the trace to extract session data.
the enterprise reflected by the network trace. 7. (optional) Run Ragator on the Argus file to col-
lapse redundant session records.
The purpose of this article is to introduce Struc- 8. Run Racount on the Argus file to count session
tured Traffic Analysis (STA). STA is a top-down records.
approach to examining network traces that builds 9. Run Rahosts on the Argus file to list all IP ad-
upon the author’s work on Network Security Moni- dresses.
toring (NSM) 1. STA has been successfully used to 10. Run Ra on the Argus file to enumerate source
analyze traces for NSM, network incident re- IP, destination IP, and destination port combina-
sponse (NIR), and network forensics (NF). STA is tions.
not by itself sufficient to perform NSM, NIR, or NF, 11. Run Ra on the Argus file to observe session
but the STA methodology applies any time an ana- data directly.
lyst must make sense of a network trace. After 12. Run Tcpflow on the trace to rebuild full content
reading this article, you may share the sentiments data of interest.
of a student in one of the author’s recent classes 13. (optional) Run Snort on the trace to generate
who said “I’m embarrassed I ever used Ethereal to alert data.
start network analysis!”
www.insecuremag.com 6
The next section will explain each of these steps 1. Make a new directory on the analysis platform
in detail. In this example, the trace provided by the specifically for the investigation at hand.
client is called sample.
$ mkdir 2005-041-santini_air
$ cd 2005-041-santini_air
Create a new directory for every trace to be ana- Do not rename the trace file.
lyzed. Name the directory using a convention that
makes sense for you, such as YYYY-MM-DD- 2. Copy the trace into the analysis directory and
CASE_NUMBER-CLIENT_NAME. change the trace permissions to read-only.
$ cp /cdrom/sample /home/analyst/2005-041-santini_air
$ ls -al
total 96
drwxr-xr-x 2 analyst analyst 512 Jul 17 16:00 .
drwxr-xr-x 5 analyst analyst 1024 Jul 17 16:03 ..
-rwxr-xr-x 1 analyst analyst 93506 Jul 16 20:38 sample
$ chmod 444 sample
$ ls -al
total 96
drwxr-xr-x 2 analyst analyst 512 Jul 17 16:00 .
drwxr-xr-x 5 analyst analyst 1024 Jul 17 16:03 ..
-r--r--r-- 1 analyst analyst 93506 Jul 16 20:38 sample
Never analyze original copies of traces unless takes that could damage the trace or alter the re-
those traces are stored on read-only media. By sults of the investigation.
changing the permissions of a copied trace to
read-only, the analyst guards against simple mis- 3. Hash the trace and copy the hash elsewhere.
$ sha256 sample > sample.sha256
$ cat sample.sha256
SHA256 (sample) =
1a6da6a2a849eb27fb7522939afab63ec59bcdb9412c2460fe611543b573d95f
$ cp sample.sha256 /home/analyst/hashes/
Here we use the FreeBSD tool sha256, since rity of the data being inspected; they reveal evi-
problems with MD5 and SHA1 have been report- dence of tampering or corruption when run on
ed2. By generating a hash and storing it else- modified files.
where, other analysts can be sure they are in-
specting the same trace should a second investi- 4. (optional) Run Capinfos on the trace to acquire
gation be required. Hashes also ensure the integ- initial statistical data.
$ capinfos sample > sample.capinfos
File name: sample
File type: libpcap (tcpdump, Ethereal, etc.)
Number of packets: 1194
File size: 93506 bytes
Data size: 213308 bytes
Capture duration: 342.141581 seconds
Start time: Thu Jun 23 14:55:18 2005
End time: Thu Jun 23 15:01:01 2005
Data rate: 623.45 bytes/s
Data rate: 4987.60 bits/s
Average packet size: 178.65 bytes
www.insecuremag.com 7
This step is optional because much of the same in the trace, and the size of the trace. This data
data is obtained using Tcpdstat below. However, helps an analyst gain an initial sense of what data
Capinfos is packaged with Ethereal, and hence is available.
available on Windows. It is good to have Capinfos
available as an alternative tool. The most impor- 5. Run Tcpdstat on the trace to obtain basic statis-
tant aspects of Capinfos statistical data include tical data.
trace start and end times, the number of packets
$ tcpdstat sample > sample.tcpdstat
$ cat sample.tcpdstat
DumpFile: sample
FileSize: 0.09MB
Id: 200506231455
StartTime: Thu Jun 23 14:55:18 2005
EndTime: Thu Jun 23 15:01:01 2005
TotalTime: 342.14 seconds
TotalCapSize: 0.07MB CapLen: 68 bytes
# of packets: 1194 (208.31KB)
AvgRate: 5.08Kbps stddev:30.22K
### IP flow (unique src/dst pair) Information ###
# of flows: 66 (avg. 18.09 pkts/flow)
Top 10 big flow size (bytes/total in %):
20.0% 16.3% 15.7% 12.9% 4.8% 4.0% 2.9% 1.3% 1.3% 1.2%
### IP address Information ###
# of IPv4 addresses: 68
Top 10 bandwidth usage (bytes/total in %):
69.9% 21.5% 18.5% 17.5% 16.9% 13.9% 5.4% 5.2% 4.5% 4.3%
# of IPv6 addresses: 4
Top 10 bandwidth usage (bytes/total in %):
81.5% 59.2% 40.8% 18.5%
### Packet Size Distribution (including MAC headers) ###
>>>
Dave Dittrich’s Tcpdstat is helpful because the sta- to the nature of the trace 3. In addition to the data
tistical data it provides gives the first real insights also available in Capinfos, Tcpdstat provides a
www.insecuremag.com 8
useful Protocol Breakdown. The number of proto- most 56% unrecognized TCP traffic. Details such
cols recognized by Tcpdstat is relatively small, and as these give an analyst a starting point for sub-
the breakdown is based on ports and IP protocols. sequent inspection.
Nevertheless, irregular patterns can often be de-
tected. Notice that the sample trace features al- 6. Run Argus on the trace to extract session data.
$ argus -r sample -w sample.argus
This step provides session data using Carter specified file in Argus format. Only tools packaged
Bullard’s Argus 4. The analyst does not yet look at with Argus can read its output.
the session records. That will happen in step 11,
once sessions of interest can be more easily iden- 7. (optional) Run Ragator on the Argus file to col-
tified. The -w flag writes session records to the lapse redundant session records.
$ ragator -r sample.argus -w sample.argus.ragator
When a particularly large trace is being analyzed, ther the sample.argus or
it may be helpful to collapse redundant session sample.argus.ragator file. For the sake of
records using the Ragator program packaged with consistency, examples that follow inspect the
Argus. The Argus server generates multiple en- sample.argus file.
tries for longer sessions. Ragator will combine
these into a single entry. In the following steps the 8. Run Racount on the Argus file to count session
analyst can run the various “Ra” tools against ei- records.
$ racount -ar sample.argus
racount recs tot_pkts src_pkts dst_pkts tot_byt src_byt dst_byt
tcp 50 884 634 250 178162 49818 128344
udp 46 94 94 0 17237 17237 0
icmp 6 7 7 0 546 546 0
ip 3 3 3 0 126 126 0
arp 159 176 175 1 10560 10500 60
non-ip 27 30 30 0 4367 4367 0
sum 293 1194 943 251 210998 82594 128404
The Racount utility breaks down the number of single packet. The -a flag tells Racount to show all
session records by protocol. This session meta- protocols.
data helps the analyst get a better sense of the
contents of the trace, again without looking at a 9. Run Rahosts on the Argus file to list all IP ad-
dresses.
$ rahosts -n -r sample.argus > sample.argus.rahosts
$ wc -l sample.argus.rahosts
129 sample.argus.rahosts
$ cat sample.argus.rahosts
0.0.0.0
0.43.224.0
1.2.170.51
4.0.0.0
4.0.255.255
10.10.3.11
15.0.56.247
15.0.246.214
...edited...
216.74.132.13
255.255.255.255
www.insecuremag.com 9
The Rahosts utility lists all of the IP addresses The -n flag disables hostname resolution.
seen in an Argus file. This process helps the ana-
lyst get a grip on the scope of the investigation by 10. Run Ra on the Argus file to enumerate source
seeing a summary of all IP addresses present in a IP, destination IP, and destination port combina-
trace. tions.
$ ra -nn -r sample.argus -s saddr daddr dport proto
| sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | uniq -c >
sample.argus.saddr-daddr-dport-proto
$ cat sample.argus.saddr-daddr-dport-proto
1 0.0.0.0 255.255.255.255.67 udp
4 0:4:0:92:90:da ff:ff:ff:ff:ff: 0
1 0:4:0:92:90:da ff:ff:ff:ff:ff: 3307
...edited...
1 1.2.170.51 16.74.132.12.80 tcp
1 1.2.170.51 16.74.132.13.80 tcp
7 1.2.170.51 6.5.161.250.80 tcp
1 1.2.170.51 216.74.132.13.21 tcp
...truncated...
This first invocation of Ra helps the analyst under- Identifying suspicious outbound connections is
stand what sources are talking to what destina- one way to perform extrusion detection, which is
tions, using what protocols and services 5. Source the process of identifying unauthorized activity by
ports are ignored at this stage of the investigation. inspecting outbound network traffic 8.
Often this session data is sufficient to identify sus-
picious activity 6. Here the analyst wishes to know 11. Run Ra on the Argus file to observe session
why 1.2.170.51 decides to connect to data directly.
216.74.132.13 using File Transfer Protocol 7.
$ ra -nn -L0 -A -Z b -r sample.argus -A -Z b - host 216.74.132.13
StartTime Type SrcAddr Sport Dir DstAddr Dport
SrcPkt DstPkt SAppBytes DAppBytes Status
23 Jun 05 15:00:40 tcp 1.2.70.51.49129 -> 216.74.132.13.21
4 2 0 0 FSA_FSA
23 Jun 05 15:00:41 tcp 1.2.70.51.42939 -> 216.74.132.13.21
13 10 4207 946 FSRPA_FSPA
If the analyst identifies one or more interesting • -A prints counts of application data passed by
sessions in step 10, he may wish to run Ra with each party. The default invocation of Ra counts
one or more host or network filters. In the example packet header bytes as data.
above, the analyst decides to look for traffic involv- • -A Z tells Argus to show TCP flag records.
ing host 216.74.132.13. The Ra switches have the • – host 216.74.132.12 is a host filter. Alterna-
following meaning: tively, a network filter like – net 216.74 could have
been applied.
• -nn disables resolution of IPs to hostnames and
port numbers to words. 12. Run Tcpflow on the trace to rebuild full content
• -L0 prints column headers. data of interest.
$ tcpflow -r sample -c port 21
DST: 220 Serv-U FTP Server v5.1 for WinSock ready...
SRC: USER example
DST: 331 User name okay, need password.
SRC: PASS example
DST: 230 User logged in, proceed.
www.insecuremag.com 10
SRC: SYST
DST: 215 UNIX Type: L8
SRC: FEAT
DST: 211-Extension supported
DST: AUTH TLS
...truncated...
Jeremy Elson’s Tcpflow rebuilds TCP sessions 9. the screen. The sample here shows an FTP ses-
When used with the -c switch, it sends the results sion. The DST is the FTP server and the SRC is
to standard output. When the -c switch is omitted, the FTP client.
Tcpflow rebuilds each side of the session into indi-
vidual files in the analysis directory. For initial in- 13. (optional) Run Snort on the trace to generate
vestigation, the author prefers sending results to alert data.
$ snort -r sample -c /usr/local/etc/snort.conf -l . -b
Marty Roesch’s Snort can generate alert data as a TCP-based flows can be rebuilt using Tcpflow.
fast way to identify low-hanging security fruit. Sus- Should any sessions require direct packet-by-
picious traffic identified by Snort can be examined packet analysis, Ethereal is a good choice. The
using session data in step 11 or full content data in trace or an excerpt can be loaded into Ethereal for
step 12. examination of the specific packets of interest.
Had the analyst simply started with Ethereal, he
An analyst who must perform zero-knowledge as- may have had little or no idea where to begin his
sessments of network traces will be well-equipped investigation.
to understand network traffic after completing the
STA process. The analyst will have gathered sta- STA forms the backbone of the investigation proc-
tistical, session, full content, and possibly alert ess the author uses for network forensics, but that
data on the trace. Session data often reveals con- is a topic for another article 10.
versations that demand additional attention, and
Richard Bejtlich (richard@taosecurity.com) is founder of TaoSecurity (www.taosecurity.com) and the TaoSecu-
rity blog (taosecurity.blogspot.com), author of The Tao of Network Security Monitoring and Extrusion Detection,
and co-author of Real Digital Forensics.
References
(1) The Tao of Network Security Monitoring: Beyond Intrusion Detection by Richard Bejtlich
(2) www.freshports.org/sysutils/freebsd-sha256/
(3) staff.washington.edu/dittrich/talks/core02/tools/tools.html
(4) www.qosient.com/argus
(5) Thanks to Paul Heinlein for his IP address sorting syntax at http://www.madboa.com/geek/sort-addr/.
(6) In a recent trace the author discovered thousands of sessions to port 3789 TCP. These connections repre-
sented traffic to a back door.
(7) This is only an example for this article. One could imagine any sort of anomalous outbound or inbound
session prompting an analyst to desire a closer look.
(8) Extrusion Detection: Security Monitoring for Internal Intrusions by Richard Bejtlich.
(9) www.circlemud.org/~jelson/software/tcpflow/
(10) Real Digital Forensics: Computer Security and Incident Response by Keith Jones, Richard Bejtlich, and
Curtis Rose.
www.insecuremag.com 11
Are Access Control Lists the Next Big Thing for Apple's new Tiger Server?
Matt Willmore explains ACL's and how they can benefit OS X Server admins
and regular users alike.
Access Control Lists (ACLs) are an improved way Stored in Metadata
of managing access to objects and directories in a
file system. Instead of the traditional UNIX-style Coinciding with the release of support for extensi-
approach of read/write/execute, ACL’s give admin- ble metadata in Tiger, ACEs (access control en-
istrators an unprecedented amount of control over tries) are stored in that very fashion. Unfortunately,
how file and directory permissions are managed. Apple has chosen to not allow tools like xattr,
ACLs have been existent in server Operating Sys- which can view and edit that metadata, to see
tems such as Windows and OpenVMS for some ACE entries. According to John Siracusa’s review
time; this is one area where Apple is playing catch of Tiger, they’re most likely prefixed with the re-
up. Luckily, Apple has done a thorough job of add- served system namespace and therefore not edit-
ing ACL support without any headaches on the able with xattr.
part of the user.
Using ACL’s with Tiger
Why Should I Care?
Unlike some file systems that require you to re-
True File Access Management format the drive to support ACLs, with Tiger you
can turn ACL support on or off with a simple com-
ACLs bring about fine-grained permissions for ob- mand. Besides the obvious ease of use, one im-
jects and directories, something that OS X has mediate benefit is that if you ever get yourself
been sorely lacking up to now. Without ACLs, stuck — say, a file that cannot be deleted by root,
server administrators are limited to the standard which you can certainly do — you can just turn
UNIX permissions: one owner, one user and ACLs off, and Tiger will go back to observing the
allowance/denial to read, write and execute ob- standard UNIX permissions. The only requirement
jects and directories. While these permissions are that Apple makes — besides Tiger, of course — is
often adequate for a single user, they rarely fit the that the volume be formatted as HFS+. Since
needs of an organization. ACLs allow admins to ACEs are stored in extended attributes (see
more accurately recreate the structure of an or- “Stored in Metadata” above) Apple needs an
ganization when defining permissions. HFS+-formatted drive to store the entries.
www.insecuremag.com 13
To enable ACLs on the client (non-server) version this case, /) and the -e flag tells fsaclctl to
of Tiger, you’ll have to use fsaclctl. To enable enable support. Additionally, you can mirror the
ACL support on the boot volume, for example, you command on all HFS+ volumes at once by adding
would use fsaclctl as follows: the -a flag. To disable support for a volume, sub-
stitue -d for -e.
sudo fsaclctl -p / -e
In Tiger Server, you have the added benefit of a
Because the command affects a system-level GUI front for enabling or disabling ACL support on
property of the file system sudo will be required. each volume.
The -p flag states the path of the mount point (in
Apple has also added an API for integrating ACLs • writesecurity: Write an object’s security informa-
into programming for OS X. Details are available tion (ownership, mode, ACL).
on the acl manpage. Also, note that API calls • chown: Change an object’s ownership.
ending in _np indicate that the routine is non-
portable; that is, it differs from the standard Directories
POSIX.1e library for ACL’s. (Apple’s implementa-
tion of ACL is based on the POSIX 1003.1e draft • list: List entries.
and is extensible for future improvements and ad- • search: Look up files by name.
ditions.) • add_file: Add a file.
• add_subdirectory: Add a subdirectory.
Before You Go Nuts… • delete_child: Delete a contained object.
Once you have ACL support enabled for a particu- Files
lar volume, we’ll use chmod to change ACL entries
on Tiger. Don’t immediately go nuts and start • read: Open for reading.
changing everything you can find; rather, let’s first • write: Open for writing.
look at what attributes can be set with a particular • append: Open for writing, but in a fashion that
ACE. The manpage for chmod lists 17 distinct at- only allows writes into areas of the file not previ-
tributes, separated into sections: ously written.
• execute: Execute the file as a script or program.
File System Objects
Interitance (Directories Only)
• delete: Delete the item. Deletion may be granted
by either this permission on an object or the dele- • file_inherit: Inherit to files.
te_child right on the containing directory. • directory_inherit: Inherit to directories.
• readattr: Read an objects basic attributes. This • limit_inherit: This flag is only relevant to entries
is implicitly granted if the object can be looked up inherited by subdirectories; it causes the directo-
and not explicitly denied. ry_inherit flag to be cleared in the entry that is in-
• writeattr: Write an object’s basic attributes. herited, preventing further nested subdirectories
• readextattr: Read extended attributes. from also inheriting the entry.
• writeextattr: Write extended attributes. • only_inherit: The entry is inherited by created
• readsecurity: Read an object’s extended security items but not considered when processing the
information (ACL). ACL.
www.insecuremag.com 14
Let’s Try This Out Sort of a pain to retype the exact argument, isn’t
it? We can speed things along by referencing the
To start working with ACLs, let’s take a simple ap- argument’s number instead! If we look back to our
proach by working on files used just for practice. example, we see that there’s only the write/
Create a new empty file with touch, and look at append allowance left. Instead of retyping the ar-
the permissions with ls -al. You can see that gument and using the -a flag, let’s reference the
the user logged in is the owner, (in my case) the number. We can do this by replacing the -a flag
user is also the group and the permissions are set with -a#; the pound sign signifies that a number is
to 644 (owner [me] can read/write, group and eve- being used instead of the string to reference the
ryone can both read). Without modifying the stan- argument.
dard UNIX permissions, we’ll change it so the
group “admin” has access to write to and append chmod -a# 0 file
the file but not read it. Accomplish the first part
with this command: Using ls -le will now not show any ACEs, but
note that there is still an ACL attached to the file;
chmod +a "admin allow write,append" it’s simply empty right now. There are many other
file cool things that you can do with chmod; to learn
more, man chmod is all you need (skip down to
Use ls -le (the -e flag instructs ls to print the ACL Manipulation Options).
ACL associated with each file that has one) to
view the directory again, and you’ll see that a plus Inheritance
“+” has been added to the listing for that file. Also,
below the file the ACL is printed; in this case it will Inheritance is one of the trickier components of
be “0: group:admin allow write,append”. ACLs. By default, no inheritance is used when as-
signing an ACL. You can change that, however, by
Also note that ACLs do not have the ability to dif- specifying an inheritence preference in the third
ferentiate between a user and group with the part of an ACL entry with the standard permis-
same name. While this is common sense for most sions.
people, occasionally there will be an instance
where a name is used by both. Avoiding this will • file_inherit just says that files created in the di-
avert a lot of problems. rectory will inherit the ACL entries of the parent
directory.
Notice how we never modified the UNIX permis- • directory_inherit is the same as file_inherit, but
sions? One thing to note here is that the ACL ar- for directories.
guments are evaluated before the UNIX permis- • limit_inherit specifies that only the immediate
sions; if there’s no matching ACE, the system then subdirectories and files of the parent directory will
evaluates the request based on the UNIX permis- inherit its ACL entries.
sion settings. only_inherit states that the directory containing the
only_inherit ACL entry will not be affected by the
Now let’s complete the other half: declaring that entry, but subdirectories and files will.
the admin group does not have the right to read
the file. We can express that as so: However, it’s also peritent to remember that the
inheritance is “static”, which means that permis-
chmod +a "admin deny read" file sions will only be applied the first time that the
subdirectory or file is created; subsequent
By using ls -le again, we can see that the new changes to the parent’s ACL listings will not affect
rule has been inserted. But why is it before our existing subdirectories and files (although new
first rule? As it turns out, there’s a specific order in ones will certainly inherit the updated listings).
which these arguments are evaluated. The correct
canonical order is user-deny, user-allow, group- Summary
deny and group-allow. ACL entries can be entered
at custom points using the +a# flag. The introduction of Access Control Lists into OS X
Tiger is very exciting to say the least. Once a sub-
This is definitely something to keep in mind when ject of much want by administrators used to the
designing your permission structure with ACLs. flexibility and power of ACL’s in other (arguably)
Now let’s say we want to get rid of the entries we industrial-strength server OS’s like Windows 2003
just created and not delete the file, but just remove Server, ACLs bring a strong, relevant tool to the
the ACEs. We accomplish this with chmod again: OS X server toolbox and allow administrators to
chmod -a "admin deny read" file much more accurately match server permission
www.insecuremag.com 15
structures to represent their company’s organiza- recognition, this is one tool that OS X Server ad-
tional structure, and is scalable enough to do so mins should take a very long look at and consider
well for small and enterprise companies alike. Al- integrating into their OS X Server setup.
though Apple has failed to give ACLs their due
Matt Willmore is a graduate student pursuing is Master's degree at Purdue University. When not writing for
MacZealots.com, Matt does Macintosh support for Purdue's Engineering Computer Network. He is also a Staff
Resident on campus and Vice President of the Purdue Mac Users Group. Matt hails from Columbus, Indiana.
www.insecuremag.com 16
Ending Spam
by Jonathan Zdziarski
No Starch Press, ISBN: 1593270526
This is yet another spam related book we are taking a look in (IN)SECURE Maga-
zine. It is obvious that spam is one of the major Internet problems, so besides the
countless products and services developed around the globe, we also see an in-
crease in books that discuss spam.
Although I believe that many of titles that deal with spam in general are not very
good, there are publications like this one that proved to be a very good read. Be-
sides giving a pretty insightful view on spammer techniques, the book's value is the
vast coverage of mathematical approaches to spam filtering.
Network Security Hacks
by Andrew Lockhart
O'Reilly, ISBN: 0596006438
O’Reilly Hacks are one of my favorite IT books. From the first one I came across
(Flickenger’s Wireless Hacks), to this one, Hacks series provides continuity in quality
information. Network Security Hacks features 100 hacks specifically connected to
network security.
The majority of info is connected to *NIX based systems, but there is also a good
portion for Windows people. Besides the cool tips on general secure networking, the
book hosts some good sets of info on intrusion detection and tunneling. This is a
book every security professional should have on their bookshelf.
www.insecuremag.com 17
Linux Desktop Hacks
by Nicholas Petreley and Jono Bacon
O'Reilly, ISBN: 0596009119
As this is the second "Hacks" book mentioned in this issue of (IN)SECURE, I will limit
my scope on mentioning just some of the good tips and tricks you can learn from it.
Here are some interesting tidbits: reduce OpenOffice.org startup time, trigger on-
screen events with some applications, accelerating remote X applications, twitching
KDE and GNOME windows managers, view PDF and Word files within Mutt, connect
to Microsoft PPTP VPN's and my favorite setting up a custom Con Konivas Over-
loaded kernel.
The Symantec Guide to Home Internet Security
by Andrew Conry-Murray and Vincent Weafer
Addison-Wesley Professional, ISBN: 0321356411
The majority of global internet security problems are related to home users. Vi-
ruses, trojans, worms, spyware, evil “hackers”, the list goes on and on.
As the most important thing in this situation is proper education, books like these
come really handy. This is a very easy to read manual on basics of home Internet
security. Besides extending the reader’s knowledge on subjects like firewalls and
identity theft, the authors give tips and suggestions on preventing problems, as
well as fixing them.
Linux: Security, Audit & Control Features
by K.K. Mookhe and Nilesh Burghate
ISACA, ISBN: 1893209687
This book is light reading material that doesn’t go too deep into details, but provides a
rather good overview of Linux operating system with emphasis on security control and
auditing issues.
This isn’t a technical Linux security book, but a very nicely written introduction to the
major high-level aspects of Linux security. The book is published by Information Sys-
tems Audit and Control Association (ISACA) and it is not widely available. You can get
your copy from the ISACA web site – www.isaca.org.
www.insecuremag.com 18
SSL VPN: Understanding, Evaluating And Planning Secure, Web-based Re-
mote Access
by J. Steinberg and T. Speed
Packt Publishing, ISBN: 1904811078
SSL VPNs became quite a hit in the last couple of years. When you take a look at
acquisitions and mergers, you will see that majority of early SSL VPN developers
were acquired by larger companies.
This book is quite a good read, as it is concise and straight to the point. The
author shows clear advantages of SSL VPNs and discusses various facts sur-
rounding this technology. Although the book has just above 150 pages, it contains
everything you should need to know on SSL VPNs.
Rootkits: Subverting the Windows Kernel
by Greg Hoglund and Jamie Butler
Addison-Wesley Professional, ISBN: 0321294319
I remember meeting Greg Hoglund at RSA Conference in San Francisco a couple
of years ago. He was promoting a book he previously co-wrote "Exploiting Soft-
ware". In a short interview we've done with Greg, he had a lot of thoughts on root-
kits and mentioned that he is going to write THE book about them. Fast forward two
years – Hoglund and Butler wrote a perfect read that goes very deep into tactics
used by rootkits.
Their main idea is not to cover specific pieces of malware, but go through all the
concepts that rootkits normally use. As a sidenote, the book focuses on Windows
kernel rootkits.
Protect Your Windows Network: From Perimeter to Data
by Jesper M. Johansson and Steve Riley
Addison-Wesley Professional, ISBN: 0321336437
Johansson and Riley are both Senior Managers in security units of the Redmond
giant. As they are quite experienced in topics surrounding Windows security, their
combined knowledge provides the reader with one of the better and most complete
guides on fortifying a Windows network.
While the content is not based on step-by-step instructions, the authors use a num-
ber of examples and case studies to prove their points and help administrators to
clearly understand all the aspects of their job.
www.insecuremag.com 19
Through out the computing world, the need for increased wireless security is
well known and wide spread. Network security is the focus of the attention
because of the acceleration and the publicity related to network and intranet
related computer crimes. Well known are the spread of virus and more mali-
cious computer code that can shut down or even destroy a computer data
centers ability to support the needs and demands of the organization. The
hysteria in the media and in public discussion is compelling but it is not a
false hysteria. The crippling affect of virus and other network attacks are quite
real and pose a genuine threat to the infrastructure of any organization.
Further, network security is under barrage from Cyber attacks from terrorist organizations is a very
hackers and criminals intent upon breaking real possibility and just as dangerous and insidi-
through the firewalls and other security obstacles ous as a physical attack on a building or an act of
to access sensitive data. open warfare in the battlefield.
Whether for corporate espionage or to access fi- There is rising evidence that antagonists are tar-
nancial information for identity theft or to alter ac- geting vital infrastructure institutions such as tele-
counts, these attacks are frequent and coming at phone companies, nuclear power plants, electrical
both a greater degree of frequency and with generation facilities, government offices, water
greater sophistication as well. storage and distribution facilities, oil and gas
transportation systems and transportation facilities
In the past, security compromise to the network such as ports and airports.
was the result of hackers who were taking on the
challenge of breaking into a network for fun or The Challenge for Network Security Pro-
thrills. While these attacks were serious and de- fessionals
serving of significant response, they masked the
real threat to come. In recent years, the attacks Those charged with security of the organization
have been orchestrated by well organized crimi- must be vigilant against such attacks both from
nals intent on stealing information, damaging the without and within the organization as any portal
infrastructure of a corporation or performing other into the network must be viewed as a potential
digital violence against the infrastructure of the open door for attack. Unlike any profession or ap-
company. A final level of threat but a very serious plication area in computing, network security is
one is the classification of attacker who is doing so extraordinarily dynamic. Each new wave of net-
as an act of violence as a result of international work attacks comes at greater levels of
hostilities.
www.insecuremag.com 20
sophistication and ability to bypass, shut down or dering the flow of data or the commerce which
in other ways circumvent the most advanced pro- those systems are designed to protect.
tections network security puts into place. The
struggle is a continuous cat and mouse game with Another tier of accountability about which the net-
network security in a constant war to keep up with work professional must be concerned are layers of
the newest methodologies and technological ad- regulation that are imposed upon certain indus-
vances of hackers and computer criminals and the tries. Certain critical industries such as the finan-
adversary continuously maintaining pace with cial sector or any industry related to national de-
state of the art network protection concepts and fense or government related commerce are held
tools and finding ways to neutralize those protec- to a strict standard of security that must be main-
tions. tained to be allowed to continue to function in that
environment. The Health Care industry similarly
At the same time, that utmost security must be has a detailed regimen of security standards that
constantly maintained, enforced, monitored and not only do health care institutions must be aware
tested, all of this access control but occur without of but support organizations as well. Further, in-
interfering or even slowing down the genuine ternational standards often are imposed if the or-
value of the network to the business entity. The ganization conducts business with foreign gov-
trade off of performance for security is often one ernments or across country boundaries, particu-
that is not acceptable for the company which larly if that commerce occurs with areas of the
complicates the challenge for network security ex- world where hostilities have occurred in the past
perts. Network security needs to operate in an “in- such as the middle east. The result may mean that
visible” mode, maintaining optimum security for any given organization may be accountable to
the network, the systems that operate the comput- multiple tiers of externally imposed security stan-
ing environment and the crucial data structures dards.
that support the systems but doing so without hin-
Certain critical industries such as the financial sector or any industry related to
national defense or government related commerce are held to a strict standard of
security that must be maintained to be allowed to continue to function in that
environment.
It is the responsibility of network security profes- Risk Management
sionals to stay current on these regulations and
assure that the network security infrastructure is One methodology that is commonly employed to
compliant on a day-to-day basis and stays in sync determine real versus perceived risk is to compute
with mandated security audits to satisfy such ex- the risk using commonly accepted risk manage-
ternal security standards. ment formulas. The formula for determining busi-
ness impact analysis of risk is:
Security professionals also must content with the
dichotomy between perceived risk and genuine Risk = Threats x Vulnerabilities X Impact.
risk. Like many infrastructure functions, to an in-
come generating institution the keen eye on the Of the three variables, vulnerabilities and impact
bottom line means that the security function is of- are the most concrete. The formula can be applied
ten under tight budgetary controls. While being to each subsystem of application area. Impact
held to a high standard, the organization is reluc- would be a computed value based on the relative
tant to fund extensive security resources without value of the application to the organization and to
significant justification. what extent that application or function is business
critical. Hence, the discipline of determining the
Nonetheless, because of intense coverage of net- correct level of security would be to perform an
work security breaches, the hysteria for high levels impact analysis of the function. That exercise by
of security may be intense within the organization itself could do much to calm perceived risk.
and the security department may have a challenge
in assuring cost justifiable security without giving Vulnerabilities are more difficult to determine but
the impression of neglecting security for those security standards that are commonly used within
who feel strongly that their systems are in need of the security industry are helpful in gauging what
additional protection. level of vulnerability is permitted within any net-
work security system.
www.insecuremag.com 21
Some vulnerabilities are tolerable and necessary While automated procedures clearly are the wave
to permit fluidity in the movement of data and of the future in I.T. auditing, some level of manual
communications through the network. Further, if inspection of the outcome will always be neces-
the impact analysis comes back with a low level of sary.
impact for the application, vulnerabilities may be
permitted because plugging those security gaps is The automation process does not remove the
just not justified. judgment and analysis that only a human auditor
can bring.
The level of threat is the most difficult to gauge but
security mechanisms already in place should be Moreover, it facilitates a greater efficiency when
able to provide statistics on the amount, severity the manual auditor steps in by automating the
and frequency of attempted security breaches. data gathering and some level of key indicator
Those statistics can be used to complete the for- evaluation so that the most common audit triggers
mula and provide each functional area of the en- are handled by the automation software thus re-
terprise with a fairly reliable risk analysis by func- serving the high-level skills of the network security
tion or application area. auditors for the types of problems that demand
their unique contributions.
I.T. Auditing
Scripts have their role in auditing of the network
Historically the approach to I.T. Auditing has been infrastructure because they remove much of the
slow to move toward automated solutions. How- tedium of data gathering.
ever, with the advent of network dominated sys-
tems, auditing techniques have evolved as well. To In script driven data collection is the only practical
date the three most common approaches to audit- way to perform a continuous monitoring of such a
ing have been manual audits and script based fast moving and fast changing environment of a
auditing and network availability scanners. network. But keeping in place certain customized
software snifters, bots, spies or other types of
The manual audit which can trace its roots back to scripts, security data that flows through the net-
the heart of auditing in the accounting world is one work on a continuous basis can be collected,
that gives the auditor a high sense of confidence evaluated and responded to.
that the audit is complete.
Historically the approach to I.T. Auditing has been slow to move toward automated
solutions. However, with the advent of network dominated systems, auditing tech-
niques have evolved as well.
Alert and alarm triggers can be very useful within rent methodology. By applying an independent set
the monitoring scripts but those too are under the of standards to the structures and systems in
constant review and control of network security place today, the areas of potential improvement
and auditing expertise. So in that way, scripts sim- will surface quickly. In that way, we know where
ply serve as an extension of the arm of manual we need to apply automation and our efforts are
auditors. efficient in terms of time, labor and cost needed to
keep the infrastructure secure.
Requirements for an Automated Solution
Secondly, these criteria can become the basis for
Network security automation and management is evaluation of potential solutions. The marketplace
an area of the enterprise that is under constant is rich with products and vendors who are skilled
review, improvement and scrutiny. in showing the need and effectiveness of their so-
lution for your network security.
If the reader is researching automating I.T. secu-
rity audits as a new initiative or as a continuous While each solution no doubt has its value, the
process of network infrastructure review and up- appropriateness of each solution should be evalu-
grade, the requirements for a viable solution re- ated by the same criteria so as to “level the play-
main the same. ing field” so to speak and assure that solutions
selected and purchased or leased are the correct
The following six criteria then can be used in two fit to your particular network problems.
ways. First, they can be used to evaluate the cur-
www.insecuremag.com 22
CRITERIA 1 – Efficiency not only places the whole of the security picture
under audit on a continuous basis rather than on
By automating security procedures, much of the an ad hoc basis, it gathers thorough data samples
day in, day out hands on operational and evalua- and is must be able to compile, evaluate and
tive activities needed by personnel within the se- model that data in an accurate fashion. When
curity or operations area is minimized. This im- evaluating security systems, whether in place or
proves the use of highly trained and expensive under consideration, those systems must deliver
human resources. results that line up with observed reality within the
systems themselves.
Not only is this good for the enterprise by reducing
the overhead for operations of security, it utilizes The ability to gather, store, report and respond to
staff at their most valued level which is good for divergent data in a timely and accurate fashion is
the individuals involved in maintaining the security the backbone of the value of an automated secu-
and ongoing health of computing systems for the rity plan.
business entity.
CRITERIA 2 – Compliance CRITERIA 5 – Auditing Frequency
As we mentioned before, security policy and pro- As mentioned above, because security data is col-
cedures can be quite strict and the security team lected continuously by automated security data
may have multiple tears of security compliance collection agents, the frequency of reporting can
from the enterprise and from external auditing en- be continuous.
tities that impose standards upon the organization
to be allowed to conduct business in a secured Reporting on a daily, weekly and monthly data us-
marketplace. Auditing to the level of maximum ing standardized and automated web based re-
compliance with these standards using manual porting can transform the auditing process from an
audit techniques is inefficient and seldom is able infrequent intrusive activity to an ongoing fact of
to sustain compliance in an ongoing fashion. life in the security environment.
Well designed automation can utilize internal alert Further, management reporting from that same
and alarm compliance rules that can be fine tuned database of security metrics can produce inquiry
as regulations change or new threats are identified driven reports for management or auditing agen-
and protected against. In this way, compliance be- cies that must hold the security infrastructure to
comes a daily standard rather than something that high levels of policy compliance.
is corrected after each manual audit.
The reliability and integrity of the automate solu-
CRITERIA 3 – Standardization tion must be beyond question to achieve the high
levels of reporting and response that we are call-
Modern computer systems and networks are di- ing for in this criteria list.
verse in nature, design and operation across the
network and the enterprise. If each of these sub- CRITERIA 6 – Flexibility
systems is audited using tools unique to that sys-
tem, there is no standard methodology to deter- The infrastructure of a complex I.T. environment
mine if each element of the network is at the same will have a wide array of systems, operating envi-
level of compliance. Any automation solution must ronments and components. The automated solu-
utilize a single measurement system and provide tion must be able to adapt to the operating system
translation of security data that is peculiar to each in which it is performing, function with little impact
subsystem back to a single measurement and re- within that setting and report interpreted data back
porting logical system. In doing so, the auditing to the auditing console without difficulty.
team can evaluate the entire infrastructure against
a single logical scheme and not have to learn nu- Furthermore, as the infrastructure evolves and
merous measurement schemes and attempt that grows, the automated auditing facility must be
translation manually. able to scale and adapt to pick up the changes in
the network and recalibrate its evaluation algo-
CRITERIA 4 – Accuracy rithms so little or no hands on effort must be made
to assure that continuous security auditing goes
Manual security audits by necessity cannot sam- on uninterrupted even in a quickly changing I.T.
ple the data stream as thoroughly as an auto- setting.
mated system. Automating the auditing process
www.insecuremag.com 23
The Process of Putting Automation into discussed under Risk Management earlier, sys-
Place tems, applications and functions can be tagged as
high, medium or low candidates for implementa-
The rationale for automating the security auditing tion of audited security based on the impact and
process is compelling. If the determination has potential risk to that system. Because the evalua-
been made to move forward with new or increased tion process is independent and devoid of bias,
levels of automation, the steps for moving forward the subsystems are judged entirely on value rather
are often similar from enterprise to enterprise. Be- than on importance to individuals within the or-
fore evaluating the solutions, conduct a study of ganization. This is far more healthy for the enter-
the current security tools and levels of auditing. prise overall than similar evaluations done manu-
This study will both identify what is of value in pre- ally that might be clouded by personal preference
sent day systems and where change would benefit or opinion. Upon conclusion of the study, the or-
the enterprise the most. Those change criteria ganization will have a detailed snap shot not only
then become the scope document for a project to of how the infrastructure looks but also its current
improve security auditing for the organization. state of security readiness and what will be the
high priority issues in developing a solution for
Further, as that study is executed and before po- automating the security infrastructure.
tential solutions are interviewed, certain standards
and security requirements will become clear. You From that study, management can be kept abreast
will no doubt have the compliance requirements of the process and be given break points to steer
already in mind particularly if compliance is a weak the process, abort it or sanction what is going on
area of the current solution. Other business and and provide funding and management support to
technical requirements for the solution to automat- push the process through to completion. A sys-
ing the security function will suggest themselves to tematic approach to the problem will increase
be added to the list already provided earlier in this management confidence that the proposed solu-
white paper. That list of requirements has three tion, even if it is an expensive one, is the right so-
applications. First, it becomes the standard lution for the organization. From that point forward,
against which all possible solutions will be evalu- the process of entertaining solutions, selecting a
ated. Second, it will provide a starting place for a software package or designing a custom devel-
list of policies to become the automation checklist oped solution and preparing a development, test-
when the pilot of an automated solution is set in ing and implementation strategy can go forward
motion. Finally, it will provide the organization sys- along familiar project management methods. But
tem for a future reporting strategy and as such because the security team has taken the initiative
give insight into the data collection and retention to bring to management solutions to the security
policies that will be important in the early design dilemma, the likelihood of success is increased
phase of the solution. tremendously and the potential that the imple-
mented solution will provide a highly secured in-
An additional parameter to be an important part of frastructure is excellent. In that way, the process of
the early study which can be viewed as a needs putting in an automated solution improves the
analysis or requirements definition project phase health of the organization as well as the health
is that a model for the criticality of systems to be and operating ability of the security department
included will emerge. Using similar definition mak- itself.
ing criteria that was part of the Impact Analysis we
Jerry Malcolm is an I.T. professional with 30 years of experience at all levels of IT project development, design,
management and documentation. Since 2003 Mr. Malcolm has been the owner/principle of Malcolm Systems
Services, an IT services consulting firm.
www.insecuremag.com 24
CNIS 2005: IASTED International Conference on Communication, Network and In-
formation Security
14 November-16 November 2005 – Phoenix, USA
http://www.iasted.org/conferences/2005/phoenix/cnis.htm
IBM European SecureWorld 2005
21 November-24 October 2005 – Prague, Czech Republic
http://www.ibm.com/training/conf/europe/secureworld
Asiacrypt 2005
1 December-4 December 2005 – Chenna, Madras
http://www.iacr.org/conferences/asiacrypt2005
Infosecurity New York 2005
6 December-8 December 2005 – Jacob K. Javits Convention Center, New York, NY
http://www.infosecurityevent.com/digitalsecure
3rd International IEEE Security in Storage Workshop
13 December – Golden Gate Holiday Inn, San Francisco, California, USA
http://www.ieeeia.org/sisw/2005
Black Hat Federal 2006 Briefings and Training
23 January-26 January 2006 – Sheraton Crystal City, Washington DC, USA
http://www.blackhat.com
RSA Conference 2006
13 February-17 February 2006 – McEnery Convention Center, San Jose, CA, USA
http://www.rsaconference.com
Black Hat Europe 2006 Briefings and Training
28 February-3 March 2006 – Grand Hotel Krasnapolsky, Amsterdam, Netherlands
http://www.blackhat.com
iTrust 2006
16 May-19 May 2006 – Piza, Italy
http://www.iit.cnr.it/iTrust2006/index.htm
www.insecuremag.com 26
Biometric security is a growing form of security used to allow physical identi-
fication, but such security measures bring up ethical issues concerning
things such as privacy, identity theft, and integrity over a remote transfer. Al-
though the security of a person's biometric is normally greater than that of a
variable data means of authentication, such as a username/password pair,
credit card number, PIN number, etc., it is less flexible and more damaging in
the event of compromise.
Introduction that the person has a right to privacy of their per-
sonal information. By requiring a person to submit
As businesses, government, and other organiza- their fingerprint to the government, or any organi-
tions look for a means to increase security to ac- zation for that matter, some people may consider it
cess data such as bank and credit card accounts, a violation of privacy. Regardless of whether or not
website membership, personal information re- a person consents to submitting a fingerprint, or
cords, etc., biometrics are becoming a popular fingerprints, the result is a copy of a unique entity,
new means to identify people 1. Some biometrics which will be kept in some sort of data store. This
are more suitable for various applications, and so data can then be used against the person in a
many different ones are used. However, each has prosecution because a fingerprint is a valid and
its own different, but similar, advantages and dis- concrete means of identification in the courts. So,
advantages. The disadvantages will be the largest consider the possibility that a crime was commit-
topic of this article, as they concern various and ted, the police dusted for fingerprints, and the fin-
debatable ethical issues. The most popular bio- gerprints incorrectly matched that of an innocent
metrics and their properties will be discussed. person.
Fingerprints How could this incorrect match happen? The first
possibility is that the software used to match the
Fingerprints are known to be unique for each per- crime scene fingerprints to a data store of finger-
son, and therefore seem to be a good means of prints made a false conclusion of the match. It is
authentication to determine that a person is who not impossible for the software to make a mistake,
they say they are. The government has been us- and more likely that it will at some point in time.
ing fingerprints for a long time to identify people Practically no software ever written has been
for various reasons, but most popularly for identi- 100% perfect, so it is possible and likely that soft-
fying criminals. Fingerprints have been used in ware used to match fingerprints will give a false
criminal investigations for more than the last 100 positive at some point. The second possibility is
years, and have been dated back as far as the that the criminal planted forged, or even fake, fin-
1500s where they were used for identification 2. gerprints.
The first issue with taking a person's fingerprint is
www.insecuremag.com 27
A fake fingerprint is most likely to come up with no gerprint. It can be done while the person is sleep-
match, but possibly could. A forged fingerprint, ing, after they touch something and walk away, or
however, is much worse (and more difficult to do) can be forcefully copied in an extreme situation.
and would falsely identify the criminal. If the crimi-
nal went out of his way enough to copy someone's The issue of false identification by fingerprint does
fingerprint and plant it at the crime scene, it is very not apply only to crime, but anywhere that a per-
probable that he/she used a fingerprint of some- son may suffer consequences that they do not de-
one they know and/or someone who would make serve. Just because the chance is normally ex-
a prime suspect for the crime. In any case, an in- tremely small, should such an issue not be impor-
nocent person could be sentenced to months, tant? Does it not matter if even one in a billion
years, or a lifetime in prison. Had the person's fin- people are falsely identified by their fingerprint,
gerprints never been required to be submitted, the and consequently suffer damages for it? If finger-
situation would have never happened. prints were to become a widespread means of
authentication, obviously something would have to
The more severe case, in which a person's finger- be done to increase security. Maybe a password
print is forged/stolen, is actually the easiest and or second biometric would be required in conjunc-
most probable means of false fingerprint identifica- tion with the fingerprint.
tion. It is not difficult at all to steal a person's fin-
Retina Scans Flughafen Frankfort Airport in Germany allow fre-
quent fliers to register their iris data to allow faster
A retina scan looks at the formation of blood ves- boarding because they can be identified quickly
sels in the back of a person's eye because the with an iris scan 2.
patterns are different for each person. Such a
scan requires a person to be very close to the
Face Recognition
scanning device and focus on a given point 1. Un-
like a fingerprint, physically replicating this data is
Currently, facial recognition is used mostly in ar-
nearly (if not) impossible. Because physical com-
eas where a small database of faces is being used
promise is not a threat, it would seem that this
for matching (usually criminals). The facial recog-
method of identification would work great. How-
nition camera looks for distinguishing facial fea-
ever, it is not convenient for the person being iden-
tures such as the distance between features
tified, and so has not become very popular.
(eyes, nose, mouth) and shape 1. In an environ-
Iris Scans ment where a person was willingly being authenti-
cated and would stand directly in front of the cam-
An iris scan analyzes features on the colored ring era, this authentication would work relatively well,
of a person's eye that surrounds their pupil. This and would obviously be easy for the person to
data can be collected much easier than a retina use. However, if the user is willing to be authenti-
scan and usually gives more accurate results 1. cated, other methods are easier and faster to
Like a person's retina, the iris is nearly (if not) im- match, and more reliable. Because of this, it is
possible to duplicate. The fallback about this used for "lookout" rather than authentication in ar-
method of identification is that the technology has eas where people walk through, and does not re-
not advanced to the point of being as usable and quire them to look at the camera or even know
easy to implement into a system as other meth- that it's there. These cameras are used commonly
ods. Currently, some U.S. state law enforcements in casinos to detect scam artists, or in places
have put iris-scanning technology to use in select where there are large gatherings of people to de-
jails and prisons. The first correctional facility to tect wanted felons and/or terrorists,
use such technology was Lancaster County Prison
in Pennsylvania, which began using it in 1994 for Each biometric has characteristics that vary in de-
prisoner identification. Since then, multiple other gree of quality. Table 11 on the following page
jails and prisons have begun using it. The gives an idea of the relative quality for common
Charlotte/Douglas Airport in North Carolina and biometrics.
www.insecuremag.com 28
Issues Regarding All Biometrics hire just about anyone with knowledge of how to
operate and maintain the data stores. Who is to
All biometrics suffer from a common security flaw say that he/she is trustworthy? A large business or
by the definition that they are a biometric. The flaw government would most likely hire experienced,
is that they are physical aspects of a person, and qualified professionals to do the same job. Their
so cannot be easily changed 1. This is good in the experience and qualifications don't necessarily
regard that it is difficult to forge/compromise, and make them any more trustworthy, although people
so a criminal cannot easily take the identity of an- generally tend to think so, and they may be right
other person. The ease of doing this varies in de- or wrong. Regardless, someone at some point
gree in different biometrics, but is especially vul- (probably more often than you'd like to think) will
nerable with fingerprints. The drawback is very leak or misuse the information. In addition to peo-
severe, however, in the event that a criminal man- ple with physical access to the data, there will be
ages to successfully forge/compromise a person's people who manage to bypass security measures
biometric. The innocent person is then left with no and gain access to the data remotely. The data-
option but to change his/her own biometric. This is base obviously cannot be stored in a biometric
a huge problem, and in the event that it occurs, scanning peripheral, so it must communicate re-
who is responsible for fixing it? And, how can it be motely to a data store. This line of communication
fixed? Unfortunately, the person responsible for is where another problem lies...
fixing it would be the victim in most cases.
Issues Regarding Biometric Information
This may be different in cases where the criminal Transfer
is the victim's employer, or anyone who is legally
responsible for the integrity of the victim's biomet- The need for remote user authentication is obvi-
ric information. For example, if a business were to ous and has been discussed. However, the trans-
authenticate its employees access to a building by fer of biometric information, regardless of the
using a biometric, and the business then misused communication method, will always be vulnerable
the employees information (i.e. to commit identity in some way. The Internet is a very popular
theft), the business may then be held responsible method for information transfer, and the informa-
for any costs associated with changing the victim's tion is available to the hands of whomever has ac-
biometric, and possibly for the damages/losses cess to the hardware used to do the transfer. Of
accrued by the criminal. Regardless of who is re- course, secure communication can be set up by
sponsible, though, it still requires that the victim encrypting the data. But, methods used to do this
change a physical aspect of his/her body. This is have vulnerabilities, and the encrypted data can
practically intolerable. be, has been, and will be compromised.
Also, where will biometric information data stores The focus of this issue is not on the details of how
be? It depends on what it is being used for, and data can be compromised, but the fact that it can
who (or what company) is in charge of the authori- and will be. In the event that this occurs, the victim
zation. In any case, how are these data stores ex- is put in a similar situation as if their biometric in-
pected to be kept secure? A small business might formation had been physically copied.
www.insecuremag.com 29
The victim cannot easily, or even possibly, de- ents are expressing concerns about their chil-
pending on the biometric, change their physical dren's privacy, and how such a proposed system
aspect(s) used for authentication. Once again, this is similar to a "big brother" scheme. The school
is an ethical issue because the victim may or may system assures them that the fingerprints will be
not have ever wanted to submit his/her personal held in a secure database, which will only be ac-
biometric information to use for authentication. Of cessible by "school district employees" and will be
course, not in all cases are people required to password protected. The point that they argue is
submit such information. But, consider an example weak not only because they don't define who or
where biometric authentication becomes wide- what a "school district employee" is, but also be-
spread for government restricted or monitored ac- cause they say the database is password pro-
cess. What if you had to provide a fingerprint, or tected. They also didn’t mention what means of
any biometric for that matter, to get access to an encryption will be used for the wireless communi-
online public library, government web page, etc.? cation between buses and the database.
Real Examples of Privacy Issues Wireless communications are notorious for being
weakly secured, so what's to stop a hacker from
To follow up on the previous section about the ex- intercepting all the student records? With all of
ample of requiring biometric authentication for re- these weak points combined, the children's private
mote government restricted or monitored access, data could be lost from being leaked by a "school
this could just as easily, and probably more likely, district employee", having the database password
happen to authenticate physical access to gov- compromised, or even having the data be inter-
ernment property. This is already beginning to cepted in wireless transit. Is it worth the chance of
happen in Tampa Bay, FL, where the school sys- losing your children's personal, unchangeable
tem (Pinellas) is considering the implementation of data just so they get on and off the right bus?
a system that would keep track of children on
school buses 3. Each child has to scan his/her fin- Some car manufacturers, such as Audi, have been
gerprint when entering and exiting the school bus developing technology that will allow keyless entry
to ensure they each get on the right bus and get and ignition of a car by the use of the owners fin-
off at the right bus stop. It also ensures that only gerprint 4. When the owner puts his/her hand on
the allowed students for each bus will be let on, so the door handle, their fingerprints are scanned and
it serves as a means of authorization. Regardless checked for authentication. Their prints are
of its purpose, the scan is required, which means scanned again when they attempt to turn the igni-
that the children do not have a choice as to tion. This all seems like a good idea because you
whether or not they want their personal physical can't lose your fingerprint like you can lose keys.
information given to the government. A parent can However, as discussed earlier, your fingerprint can
opt out from having their child's fingerprint be compromised, which gives your impersonator
scanned, but this is not the decision of the child unquestionable access to your car! Currently, un-
whose fingerprint will be taken. According to the less your keys are stolen, which is rare, a thief
article from which this information came from, par- must somehow break into a car in order to steal it,
www.insecuremag.com 30
which in most cases involves finding a way around metrics as means of enhanced security over the
the alarm (if any) and hot-wiring it to start it up. currently used methods. However, a person's bio-
Even then, a car's steering column is normally metric is private information, and protection of pri-
locked to make sure that it cannot be driven with- vacy is supposed to be supported by law. There
out keys in the ignition. Imagine that a criminal is seems to be a limited extent to which biometric
following you, and dusts for fingerprints on things authorization should expand before it becomes
that you touch. You would most likely never notice, widespread to the point where it is required by all
and, in the meantime, the criminal is making molds citizens. Who will decide where to stop, if it does?
of some sort with your fingerprints. Then, he/she The government already takes people's finger-
waits for you to go into work, the grocery store, or prints, so what will keep them from taking other
wherever, and you come back to find your car biometric information? Assuming that the govern-
missing. This seems like a lot of trouble for the ment does take such information at some point,
criminal to go through, but when it's worth $20k+, will they be responsible for the reparation of dam-
a few days, or even weeks, of work seems to be ages such as those caused by identity theft?
worth it. Given that the government would house all of the
data by some means, how are the people sup-
Conclusion posed to put full trust into the belief that their pri-
vate information is secure? The questions can
Stepping back to look at biometrics as a whole, it only be answered with time.
is evident that the opportunity exists to use bio-
Nicholas Smith is a senior college student at Georgia Southern University in the field of Computer Science. He
is interested in network applications/protocol design/security, and synchronization systems modeling. You may
contact him at nsmith22@georgiasouthern.edu.
References
(1) Liu, Simon, and Silverman, Mark. "A Practical Guide to Biometric Security Technology".
(2) "Iris Scan" – tinyurl.com/cw376
(3) Koch, Nora. "Have your thumb ready to ride the bus" – tinyurl.com/3cpdd
(4) "Audi at Forefront of Automotive Electronics Development" – tinyurl.com/ap5xk.
www.insecuremag.com 31
This (IN)SECURE Magazine article is the second of a three-part series on PDA
and Smartphone security. This second part is loosely based on the talk I gave
at this year’s RSA Security Conference 2005 in San Francisco, as well as vari-
ous review articles I have published elsewhere. However, I have updated it to
reflect many of the latest threats in the rapidly evolving mobile malware field.
Contributions to this article came from MARA members Seth Fogie, David
Hettel, Petr Matousek, and Jonathan Read, and some excerpts appear with
kind permission from InformIT.com
Overview ristic virus scanner on the PDA or Smartphone
can’t hook a specific interrupt that it might other-
At the time of this writing (September 2005), air- wise suspect is a virus.
borne viruses are increasing in sophistication at a
spectacular pace. For example, the very first Another problem is the seeming lassitude of a
Pocket PC virus to appear (Dust) was incredibly crumbling and outdated antivirus industry. The old
complex. It achieved a technological breakthrough guard antivirus industry often operates under the
equivalent to the Win32 Chernobyl virus, which antiquated principle of “security through obscurity.”
was the first PC based virus to break into the pro- Some try to keep knowledge of vulnerabilities se-
tected “Ring 0” of the Windows operating system. cret within a closed priesthood of a few selected
men. Meanwhile, hackers, identity thieves and vi-
Moreover, less than a year after Dust, we have rus writers may have access to the same informa-
already seen numerous “blended” threats. For ex- tion, while the larger security community is kept in
ample, virus writers have developed anti-antivirus the dark. This can become problematic in the new
trojans, and have even combined these with the world of rapidly evolving field mobile threats,
Bluetooth spreading capability of the Carib (Cabir) where millions of unprotected wireless devices
virus. So in the space of one year, we have seen a now share data promiscuously “any time, any-
viral evolution equivalent to what took 20 years on where.”
desktop PCs.
Mobile Antivirus Researcher’s Association
One problem with this rapid evolution in threats is
the fact that mobile devices can’t support sophisti- For those who have an interest in the field of mo-
cated antivirus software on current platforms. For bile malware, please consider applying to the Mo-
example, embedded operating systems don’t use bile Antivirus Researchers Association
“interrupts” (system calls to the kernel), so a heu- (www.mobileav.org).
www.insecuremag.com 32
It is open to security industry members who have executed, all application icons will vanish as if de-
a legitimate need to obtain source code and bina- leted. This is a trick, since the files still exist. In
ries of the latest mobile viruses and security vul- reality, the virus simply removed their icons from
nerabilities. MARA is a free, vendor neutral or- the display. This is similar to setting all file attrib-
ganization whose members come from the global utes to ‘hidden.’
community of professional, embedded malware
and wireless security researchers. Our research 911 Virus
and discoveries are published as full disclosure to
the security community as soon as threats can be Older handsets were relatively immune from air-
verified and tested. borne viruses because they lacked functionality.
However, Internet-enabled Smartphones are facile
The Threats hosts for infection and attack. For example, the
“911 virus” flooded Tokyo's emergency response
The following will describe the evolution of mobile phone system using an SMS (short message sys-
malware from its beginning until the present time. tem) message. The message, which hit over
We will progress more or less in chronological or- 100,000 mobile phones, invited recipients to visit a
der, as well as showing the evolution from simple, Web page. Unfortunately, when the users at-
nuisance viruses into more sophisticated ones. tempted to visit the website, they activated a script
that caused the phones to call 110, which Tokyo's
Phage equivalent of the 911 emergency number in the
United States. Thus, the virus could have indirectly
Phage was the first PDA Virus and was discovered resulted in deaths by denying emergency serv-
on the Palm OS in Sept. 2000. When the virus is ices.
executed, infected PDA files display a grey box
that covers the screen, whereupon the application SMS attacks
terminates. In addition, the virus infects all other
applications on the device. A potential vulnerability of SMS is that it allows a
handset to receive or submit a short message at
When a “carrier” device is synchronized with a any time, independent of whether a voice or data
clean PDA, the clean PDA receives the Phage vi- call is in progress. In addition, if the handset is un-
rus in any infected file. This virus will in turn copy available, the message will be stored on the cen-
itself to all other applications on the clean device. tral server. The server will then retry the handset
until it can deliver the message.
Liberty Crack
In fact, there are desktop tools that script kiddies
This virus acts as a Trojan horse because it use for SMS Denial of Service bombing, such as
comes in a disguise (although it does not open a Fruckie’s SMS “Bombah” (Fig. 1 on the following
backdoor). “Liberty” is a program that allows you page). The same principle of this tool, when cou-
to run Nintendo GameBoy games on the Palm pled to the power of a replicating virus, can poten-
OS. Liberty is shareware, but like all useful share- tially result in wide scale Denial of Service attacks.
ware it has a corresponding crack that converts it
to the full registered version. The authors of Lib- Another example of such an SMS flooding virus
erty decided to pay back the pirates by releasing a occurred in Scandinavia. When a user received
“counter-crack” for Liberty that was actually a vi- the short message, the virus locked out the hand-
rus. The developers distributed it on IRC. Unfortu- set buttons. This effectively became a denial of
nately for the pirate, when executed, the Liberty service attack against the entire system.
crack virus deletes all applications from the PDA.
Similarly, a Norwegian company found another
This virus can spread both through the desktop example of malicious code. In this case, a
and through wireless email. In fact, it may be the Norway-based WAP service developer known as
first known PDA virus to spread wirelessly in the Web2WAP was testing its software on Nokia
wild. phones. During the testing, they found that a cer-
tain SMS was freezing phones that received it.
Vapor The code knocked out the keypad for up to a min-
ute after the SMS was received. This is similar to
The “Vapor” virus does just what it sounds like it format attacks that cause crashes or denial of
should; when infected with Vapor, all the files on service attacks against Internet servers.
the PDA “disappear.” When the infected file is
www.insecuremag.com 33
Fig. 1: Fruckie’s SMS “Bombah”
Carib (Caribe, Cabir) changing the frequency 1600 times a second, it is
very unlikely two devices in the same area will
When translated into Spanish, ‘The Caribbean’ is conflict with each other.
Carib, which is also the name for the first known
Bluetooth virus that targets mobile phones. While What makes Bluetooth really useful is that it
the virus itself is relatively harmless, it represents automatically handles the connection process be-
a new era for virus writers and a new set of wor- tween two devices. By scanning the surround area
ries for mobile phone owners. for other Bluetooth devices, and by setting up a
connection between discovered devices, a piconet
While a virus can be written for a single, uncon- is created. This piconet spreads from device to
nected device, such a program will have a very device, thus creating a self-maintaining web of
short life. To keep the virus ‘alive’, it must be able connected devices.
to spread from one device to another. This part of
the virus process is called the ‘infector’ or ‘infec- While this concept is great for those who are hon-
tion vector’. est, in the last couple years several vulnerabilities
have been found within the protocol that make it
While infectors have changed and evolved over possible to extract information from users, send
the years, the most common infector is via email. users unsolicited messages, and perform other
Once infected, a virus either uses its own email miscellaneous attacks. However, up until now
engine, or borrows the victim’s email program to these ‘attacks’ have been used only in labs or to
send out copies of itself to email addresses it finds send unsolicited messages to other Bluetooth de-
on the victim’s system. Other infectors include vices (toothing).
floppy disks and pirated software. New infectors
are very rare simply because there are a very lim- Understanding Carib
ited number of new methods of communication.
Carib is the first known virus/worm that uses Blue-
In 1999 a new protocol was designed, developed, tooth as an infector. While the worm itself is basi-
and implemented into numerous mobile devices. cally harmless, it has recently been coupled with
Known as Bluetooth, the wireless communications other malware to create “blended” threats.
protocol was built to facilitate the transmission of
information within a relatively small range (about In fact, Carib is already a worm/Trojan by defini-
10 meters). Operating in the 2.45 GHz range, Blu- tion. Once a device is infected, it scans the air-
etooth uses spread spectrum frequency hopping waves for other Bluetooth enabled devices until it
(1600 hops/s) to reduce the risk of interference finds one (and only one). It then tries to send the
between one Bluetooth device and another. By new target device a copy of itself.
www.insecuremag.com 34
At this point the victim is prompted with a dialogue As a desktop analogy, many free porn websites
box as to whether or not they would like to accept use browser-based exploits to infect PC users with
the incoming file. If the victim accepts, the file will dialer trojans. This is a classic example of dialer
transfer and another prompt will be presented trojans being used for financial gain. Dialer trojans
warning the victim that the no supplier could be have been around on PCs for many years. Tradi-
verified. If the victim hits the ‘Yes’ key, the device tional PC dialer trojans rely on the infected com-
will prompt the victim one final time if it should in- puter having a working modem; and the modem
stall the program. At this point the device is in- needs to be connected to a wall socket. It was
fected. only a matter of time before someone realized that
coding dialer malware for computers that mostly
Once infected, Bluetooth is enabled on the device, rely on broadband was a waste of time. Such
in case the file is downloaded or transferred via an malware coders have now moved to cellular
alternate route. Then a splash screen is presented phones.
on the victim’s device with the message “Caribe-
VZ/29a”. Finally, the infected devices starts scan- Symbian-based cellular phones offer the ability to
ning for any new Bluetooth enabled devices that it run far more code than earlier cellphones. Cellular
can infect. phones can now be used to play games, surf the
Internet and perform many other activities tradi-
Of note, Carib will only transfer the file once. In tionally done from a desktop computer. While
addition, only Nokia Series 60 phones appear to these features are useful for consumers, it also
be vulnerable, at least according to an internal means that malware coders have an increasing
memo written by Symbian. Finally, this worm re- amount of scope in which to apply malicious code.
quires user interaction three separate times, which Code that once only worked on desktop comput-
means it would take a naïve user with a complete ers can now be easily ported to work on handheld
lack of viruses knowledge for Carib to spread. devices running the Symbian OS.
That is, until it was coupled with other malware.
Mosquito, the game that plays the player
Mosquito Trojan
We first heard of the Mosquito dialer trojan, while
The Symbian operating system powers many cel- researching online. Various web forum users
lular phones, and also supports a wide range of where complaining that they had installed a game
third party applications – including games. Unfor- and now their phones where sending text mes-
tunately, one popular game turned out to have a sages to the number 87140 (Fig. 2 below). But
“cracked” version that was secretly infected with a some users had not noticed this problem, so it
Trojan horse. The Mosquito Dialer Trojan infects was evident that there were at least two discrete
the popular game “Mosquito” with code that se- versions of this game in circulation — and that at
cretly messages pay-per-call numbers. least one of these versions was malware.
What is a dialer Trojan? The game that the infected users had installed
was called Mosquito v2.0. The game is unique in
A dialer trojan is malware coded to secretly dial that it makes use of the phone’s built-in camera.
phone numbers, thus leaving the infected victim The user walks around shooting mosquitoes in a
with a large phone bill. There are two reasons why virtual reality-like atmosphere. This game ap-
someone might code and spread a dialer trojan. peared to be a “cracked” version that appeared on
The first reason is destructive; perhaps as tool of the many cell phone warez and p2p networks that
revenge. The second reason is for financial gain. plague the Internet underground. It appeared that
Simply set up a premium 900 number and charge 87140 was a UK number costing a hefty £1.50 per
$5.99 a minute. Then, all the malicious coder text message.
needs is a few hundred infected victims to make a
decent amount of money.
Fig. 2: Screenshot of the first known mention of an infected Mosquito game (source – tinyurl.com/4ght6)
www.insecuremag.com 35
How to detect the malicious version of SisView (www.dalibor.cz/epoc/sisview.htm) is a
Mosquitoes v2 freeware plug-in that has been created for the
shareware program Total Commander
Cellular phone malware is a relatively new phe- (www.ghisler.com/download.htm). This tool allows
nomenon. There were no clear instructions that we you to view the contents of any .sis file. System
knew of for dissecting Symbian malware, and we admins can view .sis files that are stored on their
had no prior experience with this platform. But we servers to see if they have the .nfo files often as-
have developed a successful antivirus scanner for sociated with cracker group releases (pirated
a similar platform (Windows Mobile/Pocket PC), software). The malware version of the mosquito
and we have written some papers on ARM-based game is cracked, so using this method could help
reverse engineering. in initial detection.
So out of curiosity, we decided to download the Unmakesis (mitglied.lycos.de/atzplzw/) is a free-
infected warez and see if we could take a look un- ware tool for unpacking a Symbian .sis file. With
der the hood. Hopefully, by reporting our findings Unmakesis, analyzing and extracting Symbian sis
here, we will inspire others to take the analysis files is relatively easy. When using Unmakesis it is
further. important to set your screen resolution to
1024x768; the program does not dynamically ad-
For every instance of this trojan that we have en- just to your screen size and you may find that you
countered, the file is packed as a .sis file type. cannot use the functions needed to extract the sis
Specific tools are needed to view the contents of a file.
.sis file on a PC. Most of the tools are freeware
and are easily available. Using Unmakesis on the mosquito file we can see
that this file contains Mosquitos.app (Fig. 3).
Fig. 3: Using Unmakesis to extract the Mosquitos.app file
www.insecuremag.com 36
Extracting the Mosquitos.app file onto your com- written comments and hex code that the file con-
puter allows you to view the code of this file using tains. Looking at the code closely we find the fol-
the following two basic techniques. The first tech- lowing line:
nique used to view the file is hex editing. Using a
simple hex editor (Fig. 4) allows you to access Free Version cracked by Soddom bin Loader
Fig. 4: Selected hex dump of Mosqitos.app showing what appears to be the malware author
Finding the SMS call routine in the cious dialer. What we need is a more complex de-
Mosquitos.app file bugging tool. The tool we highly recommend is
IDA Pro (www.datarescue.com/idabase/). IDA
Using a hex editor gives us some preliminary in- comes up with the following SMS call routines;
formation on the file, but it does not give us these are just a few selected examples; the SMS
enough information to prove that this file is a mali- routines make up 5 pages of data, which are too
large to post here:
www.insecuremag.com 37
As you can see, the malicious game uses SMS code size, and the virus body is copied at the end
routines. That makes it one of the first docu- of the last section. Then the new EntryPoint is set;
mented trojans written specifically for cellular in other words, the pointer is set to the first instruc-
phones. At the least, it is the first Symbian-based tion to execute when the program is loaded. This
cellular phone dialer Trojan of which we know. way, it's guaranteed that the virus will be run.
Looking further at the following code snippet, the Because Dust doesn't use the host's import sec-
phone number 87140 is clearly visible, along with tion, it has to somehow obtain the needed API
other numbers that may also be SMS text targets. function addresses. This was the biggest problem
to overcome, and finding the solution took some
a9222 1000BA84 time. As soon as we have the function addresses,
a4636 1000BA90 we use them to alter the victim's files found on the
a87140 1000BA9C memory medium. Finding files to infect provides
a33333 1000BAA8 the standard function pair FindFirstFile and
FindNextFile. Together with CreateFile, they differ
There is no need for this game to use SMS rou- from their Win32 counterparts, which appeared to
tines. When combined with multiple user reports of be another minor problem.
surreptitious, paid text messages, it appears to be
a legitimate threat. Every file gets mapped into memory, where later
needed modifications are made. Windows CE in-
The Brador Trojan troduced a new function, CreateFileForMapping,
that has no equivalent on Win32. Without calling
Brador was the first backdoor Trojan for Pocket this function, there's no way to get the file handle
PC. It gives full, wireless remote control of your that could be used to create the mapping object.
Pocket PC to a remote hacker who might even be On the other hand, the advantage of the ARM ISA
on the other side of the world. This is problematic appeared – the automatic generation of position-
if, for example, you are a physician with patient independent code. On Win32 x86, you had to de-
medical records on your Pocket PC. Or, you may termine its actual memory position and use this
be a corporate executive or network admin who, value later to modify absolute variable addresses
like many, use your Pocket PC over a VPN to con- (if the host's relocations were not altered, of
trol your wired infractructure – thus potentially giv- course).
ing a remote hacker total control of your enterprise
network. The virus source code includes deeper comments
of given problems and techniques. Please take the
Brador is successful in part because the Pocket time to carefully read through the comments of
PC operating system doesn't come with a native this source code, in which I explain the Windows
process monitor. Without a process monitor (such CE .NET security weakness that allowed me to
as the Win32 Task Manager), it can be difficult to create the first successful virus for this platform.”
detect and remove this Trojan and any future Tro-
jans. Pocket PC lacks this feature; when a user For those who are interested in further details, the
attempts to delete the malicious file, the system full, annotated source code has been published by
presents an error message saying that the pro- Pearson Education, Inc. InformIT. The URL is
gram is in use. In this case, it might seem that the tinyurl.com/8zmqn
only way to remove the Trojan is a hard factory
reset (similar to formatting the hard drive on a Evolution of “blended” mobile threats
desktop PC). Fortunately, there are now third party
tools that can do this without needing a hard reset. The last few months have seen a rapid evolution
of “blended” mobile malware. Much of this activity
Dust Virus has been seen on the Symbian Smartphone plat-
form. For example, “Skulls” was the second trojan
The following is the virus writer’s description of the to infect Symbian Series 60 smart phones (the first
significant technical obstacles that prevented any- was Mosquito, discussed above). When launched,
one from successfully infecting Windows CE for the application claims to be an “Extended Theme
nearly 4 years. Manager by Tee-222.” However, it then disables all
other applications on the phone and replaces their
“While programming WinCE4.Dust, I used time- icons with a skull and crossbones. Worse, it was
tested techniques from the Win32 world. When more recently merged with Caribe to form the first
infecting, the PE file is altered in the following way: “crossover” malware for smartphones.
The last section size is increased by the virus
www.insecuremag.com 38
Skulls and Caribe also merged to form Metal only 2kb in size, and it has already seen variants
Gear, a trojan that masqerades as the game with merged with Caribe to spread to other phones.
the same name. Metal Gear uses Skulls to deacti- Other examples of viral evolution include the fol-
vate the devices antivirus. Thus, it was the first lowing:
anti-AV malware for Symbian phones. The mal-
ware also drops SEXXXY.sis to the device, an in- • Dampig trojan: Notable in that it corrupts the
staller that adds code to disable the handset menu system uninstallation settings, making it more diffi-
button. The Trojan then uses Caribe to transmit cult to remove.
itself to new devices. • Mabir virus: Similar to Cabir, but instead of Blue-
tooth it uses SMS to spread.
Another example of blending is the Gavno.a Tro- • Commwarrior: also tries to disable the onboard
jan, which is spread via a file called patch.sis (it antivirus software.
masquerades as phone patch). Gavno uses a • Frontal virus: causes a total system crash of the
malformed file to crash an internal Symbian proc- phone until it is removed
ess, thus disabling the phone.
Lastly, a new Symbian Trojan called Doomboot-A
The effect is to disable all handset buttons and to that now loads a Commwarrior variant when it in-
completely prevent the user from making calls. It fects Smartphones. Doomboot-A destroys the boot
may also cause a continual rebooting loop. It is process so that the phone is not useable.
Dr. Cyrus Peikari is the founder of Dallas-based Airscanner Corporation, which produces technologically ad-
vanced security software for PDAs and Smartphones. Dr. Peikari finished his undergraduate training with hon-
ors in electrical engineering from Southern Methodist University in 1991. He also worked as a telecommunica-
tions software engineer for Alcatel before receiving his Doctor of Medicine degree from Southwestern in 1995.
Dr. Peikari has co-authored five technical books on information security, including "Maximum Wireless Secu-
rity" from SAMS and "Security Warrior" from O'Reilly. Dr. Peikari is also a frequent speaker at major informa-
tion security conferences, including RSA, Defcon, NetSec, CISSPcon and CSI. He holds several patents and
patents pending in the mobile security field. Dr. Peikari has helped several universities start brand new infosec
degree programs. He is also the Site Host for Security at Pearson Education's InformIT.com division, where his
infosec articles are read by millions of network administrators and programmers per year.
www.insecuremag.com 39
F-Secure Antivirus Research Weblog
http://www.f-secure.com/weblog/
This blog is run by the F-Secure Antivirus Research Team whose most prominent member is certainly
Mikko Hypponen, well known in the security community. This is a great place to look for up-to-date infor-
mation on new viruses and Trojans as well as interesting facts as they are discovered. The team provides
a fresh look at the antivirus world free of marketing hype and filled with texts, screenshots and sometimes
videos. Other antivirus vendors could learn a lot from the F-Secure team.
A Day in the Life of an Information Security Investigator
http://blogs.ittoolbox.com/security/investigator/
Interesting stories of apparently real life events that sometimes make you think. The description of the
author is: “Follow an Information Security Investigator as he recounts his unique experiences working with
federal, corporate, and military institutions and provides his perspective on the security issues impacting
the IT industry today.”
SpywareInfo
http://www.spywareinfo.com/
This website is the perfect resource for information on spyware. In the words of the authors: “Has some
sleazy web site taken over your browser? Are you getting pop up ads even when your browser has been
closed for some time? Are you infected with a spyware program that refuses to go away? If so, our mes-
sage board has dozens of dedicated volunteers ready to give you step-by-step assistance to remove the
malicious software and regain control of your PC.”
Financial Cryptography
https://www.financialcryptography.com/
This is a blog that covers a topic of interest to a specific audience and it does it well. Updated regularly it
provides links to stories and commentaries that anyone interested in cryptography should find interesting.
The authors publish also original content on the blog. To give you an idea of what to expect here are two
titles of the papers linked there: “On Secure Knowledge-Based Authentication”, “An Introduction to Pet-
name Systems”.
Send your favorite security websites and blogs to editor@insecuremag.com for consideration.
www.insecuremag.com 41
As more and more computers are getting plugged into the Internet, the risk
factor associated with an online presence has also risen. The increase in
hours online combined with the propagation of always-on broadband and
high-speed cable/DSL Internet access has resulted in the need to secure even
simple, one-computer home networks. As a result, the humble firewall has
become a must-have item as opposed to a could-have item in a network.
The basic aim of a firewall is to keep unwanted dedicated machine to protect the entire network
people off of your network. The virtual wall of fire from malicious traffic. This hack explores a dedi-
is essential in keeping out crackers who want to cated firewall Linux distribution called SmoothWall,
invade your security, as well as blocking the grow- which you can install on an aging computer to
ing armies of worms, viruses, and other Internet provide a dedicated firewall appliance to protect
nasties that crawl the Web looking for computers your entire network. After the initial setup, you will
to exploit. The situation is very bad; an unpro- find your SmoothWall box to be invaluable.
tected Windows machine can become infected in
as little as four minutes after it is put on the Inter- Gather the Ingredients
net. If you are considering a firewall but are uncer-
tain you want to put the effort into it, ask a friend To create a SmoothWall firewall appliance, you
who has one for a list of attempted intrusions on need a computer to use. Anything from a ‘486 with
his network. You will probably be surprised by the 16MB of RAM on up is fine, but if you want to
frequency of attacks. My own firewall logged more keep several days’ worth of log files, I recommend
than 100 attempted intrusions in the first few hours you use at least a 4GB disk. You also need at
after I put it up. least two Linux-supported network cards in the
computer.
Both software and hardware firewalls are avail-
able. Software firewalls are installed on each Here is how you will use your network cards:
desktop on the network, and they protect that sin-
gle machine. The hardware approach is to use a
www.insecuremag.com 42
• If you have a cable/DSL modem that plugs into a Configure the Firewall
network card, you need a card for this. This card is
referred to as the RED interface. Once the SmoothWall firewall is installed, you can
access it in two main ways. The most common
• You need a network card to connect to the in- and popular way is to access its special web-
ternal network. If you have more than one com- based interface, which is available on port 81. So,
puter on your internal network, this interface is if your firewall’s IP address is 192.168.0.1, you
usually plugged into a hub, switch, or wireless ac- can access the web interface at 192.168.0.1:81.
cess point. This card is referred to as the GREEN SmoothWall’s default configuration does not allow
interface. access from outside your internal network, so you
cannot make changes to it from work or while
• If you have any computers that need to be ac- traveling.
cessed publicly, you need another network card
for these. This card is referred to as the ORANGE When you access the web interface, you are
interface and also is known as the snazzily titled asked for the administrator password for the ma-
De-Militarized Zone (DMZ), because it exists in a chine (which you created when you installed
sort of no man’s land between the public Internet SmoothWall) and then you can configure it. Within
and your private network. the web panel is a huge range of options and fea-
tures that you can configure. These options are
You should install the cards you need in the com- grouped into categories which are visible at the
puter, download the SmoothWall ISO from top of the page.
www.smoothwall.org, and then burn the ISO to
CD. If you need to do something that is not accessible
in the web interface, you can use the included
The next step is to boot from the CD and install Java SSH applet to log in to the machine and type
the SmoothWall software. If you cannot boot from in commands to an SSH shell.
the CD, try using the Smart Boot Manager. If this
does not work, you can create a series of boot Enable Port Forwarding
floppies from the files found in the images direc-
tory on the SmoothWall CD. There you’ll find two A common requirement when running a network of
boot floppy images called bootdiskone-x.x.img and machines is the need to have a connection from
bootdisktwo-x.x.img. Use dd to create the floppies outside the firewall serviced by a machine inside
(unmounting and changing the floppy between im- the firewall (usually in the DMZ). This is the sce-
ages, of course): nario for those who run a web or email server and
need to have the relevant ports accessible to the
foo@bar:~$ dd if=bootdiskone-x.x.img outside world. When a computer connects to your
of=/dev/fd0 bs=1024 conv=sync ; sync IP address/domain, the first computer that re-
foo@bar:~$ dd if=bootdisktwo-x.x.img ceives the connection is the firewall. Because it is
of=/dev/fd0 bs=1024 conv=sync ; sync unlikely you are running a web or email server on
the firewall itself (if you are, you really shouldn’t be
If you need to create the floppies on a Windows
because bugs in these programs can compromise
system, you can use the rawrite program
the security of the firewall) you need a method to
(uranus.it.swin.edu.au/~jn/linux/rawwrite.htm) to
get that request to the computer that can handle it.
create the disks. Installing SmoothWall is a fairly
This is where port forwarding comes in. Its pur-
simple process, but you need to know how you
pose is to take the request for a service and for-
want your network to be set up in terms of IP ad-
ward it to the specific machine on the network that
dresses. Within the setup routine are a Networking
can service the request.
section and an Addresses subsection. You set the
IP addresses for each interface here. For exam-
To do this with SmoothWall, access the web inter-
ple, a common setting for the GREEN interface is
face and select Networking Port Forwarding.
the IP address 192.168.0.1 and the network mask
You can leave the external source IP box blank if
255.255.255.0. The RED interface is typically set
you want to accept all connection requests for the
to DHCP to grab your Internet IP address from the
port in question (this is commonly the case for a
cable modem, but you should check with your ISP
public service such as web serving). In the Source
to see how the cable modem gets its IP address.
Port box, specify the port you want to forward
The other setting to configure is in the “DNS and
(such as port 80 for a web server). Finally, you can
Gateway settings” section. Set this to 192.168.0.1.
enter the destination computer IP address and its
Now you have your firewall set up as your Internet
port number in the other two boxes. This is quite
gateway that other machines can refer to when
useful if you want to forward a normal port 80
requiring Internet access.
www.insecuremag.com 43
connection to a machine with a different port num- firewall. Because of this a lot of organizations and
ber, such as port 8080; a common request with homes use it to protect their networks. Although
Apache virtual hosts. Once you have forwarded the GPL version of the firewall is very capable, the
your ports, you need to select the External Serv- commercial version and its included support can
ices Access page and add the ports you have for- be really useful for commercial organizations. Both
warded to that page. This enables access to the versions give you the flexibility of a powerful and
ports from outside the network. SmoothWall is supported firewall that can protect a network of
proven to be an incredibly capable and flexible Linux, Windows, or Mac OS X machines.
Excerpted from “Linux Desktop Hacks” by Nicholas Petreley, Jono Bacon (ISBN: 0596009119). Copyright
2005, O'Reilly Media, Inc. www.oreilly.com All rights reserved.
www.insecuremag.com 44
WINDOWS – Acunetix Web Vulnerability Scanner
http://www.net-security.org/software.php?id=633
Acunetix WVS first crawls the whole website, analyzes in-depth each file it finds, and displays the entire
website structure. After this discovery stage, it performs an automatic audit for common security vulner-
abilities by launching a series of web attacks.
LINUX – WifiScanner 1.0.0
http://www.net-security.org/software.php?id=381
WifiScanner is an analyzer and detector of 802.11b stations and access points. It can listen alternatively
on all the 14 channels, write packet information in real time, can search access points and associated cli-
ent stations, and can generate a graphic of the architecture using GraphViz.
MAC OS X – iStumbler
http://www.net-security.org/software.php?id=620
iStumbler is a free, open source tool for finding AirPort networks, Bluetooth devices and now mDNS serv-
ices with your Mac. iStumbler combines a compact user interface with a real time display of signal strength
and complete debugging information.
POCKET PC – Crippin
http://www.net-security.org/software.php?id=544
Crippin was designed to protect confidential files in case a Pocket PC is lost or stolen. It’s been designed
to be:
* small (minimal executable size).
* miserly (with respect to storage required both during and after encryption).
* secure (using RSA encryption).
If you want your software title included in the HNS Software Database e-mail us at software@net-security.org
www.insecuremag.com 45
Hardening a Unix system can be a difficult process. It typically involves set-
ting up all the services that the system will run in the most secure fashion
possible, as well as locking down the system to prevent local compromises.
However, putting effort into securing the services features beyond those provided by the OpenWall
that you’re running does little for the rest of the patch. grsecurity now includes many additional
system and for unknown vulnerabilities. Luckily, memory address space protections to prevent
even though the standard Linux kernel provides buffer overflow exploits from succeeding, as well
few features for proactively securing a system, as enhanced chroot() jail restrictions, increased
there are patches available that can help the en- randomization of process and IP IDs, and in-
terprising system administrator do so. One such creased auditing features that enable you to track
patch is grsecurity (www.grsecurity.net). every process executed on a system. grsecurity
adds a sophisticated access control list (ACL) sys-
grsecurity started out as a port of the OpenWall tem that makes use of Linux’s capabilities system.
patch (www.openwall.com) to the 2.4.x series of
Linux kernels. This patch added features such as This ACL system can be used to limit the privi-
nonexecutable stacks, some filesystem security leged operations that individual processes are
enhancements, restrictions on access to /proc, able to perform on a case-by-case basis.
as well as some enhanced resource limits. These
features helped to protect the system against To compile a kernel with grsecurity, you will need
stack-based buffer overflow attacks, prevented to download the patch that corresponds to your
filesystem attacks involving race conditions on kernel version and apply it to your kernel using the
files created in /tmp, limited a user to only seeing patch utility.
his own processes, and even enhanced Linux’s
resource limits to perform more checks. Since its For example, if you are running Linux 2.4.24:
inception, grsecurity has grown to include many
# cd /usr/src/linux-2.4.24
# patch -p1 < ~andrew/grsecurity-1.9.13-2.4.24.patch
www.insecuremag.com 46
While the command is running, you should see a should be returned back to the shell prompt with-
line for each kernel source file that is being out any additional output.
patched. After the command has finished, you can
make sure that the patch applied cleanly by look- After the patch has been applied, you can config-
ing for any files that end in .rej. ure the kernel to enable grsecurity’s features by
running make config to use text prompts, make
The patch program creates these when it cannot menuconfig for a curses-based interface, or
apply the patch cleanly to a file. A quick way to make xconfig to use a Tk-based GUI. If you
see if there are any .rej files is to use the find went the graphical route and used make xcon-
command: fig, you should then see a dialog similar to Fig-
ure 1–1. If you ran make menuconfig or make
# find ./ -name \*.rej config, the relevant kernel options have the
same name as the menu options described in this
If there are any rejected files, they will be listed on example.
the screen. If the patch applied cleanly, you
Figure 1–1. Linux kernel configuration after the grsecurity patch has been applied.
To configure which grsecurity features will be en- write to FIFOs that they do not own if they are
abled in the kernel, click the button labeled Grse- within a directory with permissions of 1777.
curity. After doing that, you should see a dialog
similar to Figure 1–2. In addition to the tighter symlink and FIFO restric-
tions, the Low setting increases the randomness
To enable grsecurity, click the y radio button. After of process and IP IDs. This helps to prevent at-
you’ve done that, you can enable predefined sets tackers from using remote detection techniques to
of features with the Security Level drop-down list, correctly guess the operating system your ma-
or set it to Custom and go through the menus to chine is running, and it also makes it difficult to
pick and choose which features to enable. guess the process ID of a given program.
Choosing Low is safe for any system and should The Low security level also forces programs that
not affect any software’s normal operation. Using use chroot() to change their current working
this setting will enable linking restrictions in direc- directory to / after the chroot() call. Otherwise,
tories with mode 1777. This prevents race condi- if a program left its working directory outside of the
tions in /tmp from being exploited, by only follow- chroot environment, it could be used to break
ing symlinks to files that are owned by the process out of the sandbox.
following the link. Similarly, users won’t be able to
www.insecuremag.com 47
Figure 1–2. The grsecurity configuration dialog
Choosing the Low security level also prevents identd daemon (if you are running one) as an
nonroot users from using dmesg, a utility that can account that belongs to the wheel group. Accord-
be used to view recent kernel messages. ing to the grsecurity documentation, none of these
features should affect the operation of your soft-
Choosing Medium enables all of the same fea- ware, unless it is very old or poorly written.
tures as the Low security level, but this level also
includes features that make chroot()-based To enable nearly all of grsecurity’s features, you
sandboxed environments more secure. The ability can choose the High security level. In addition to
to mount filesystems, call chroot(), write to the features provided by the lower security levels,
sysctl variables, or create device nodes within a this level implements additional /proc restrictions
chrooted environment are all restricted, thus by limiting access to device and CPU information
eliminating much of the risk involved in running a to users who are in the wheel group. Sandboxed
service in a sandboxed environment under Linux. environments are also further restricted by disal-
In addition, TCP source ports will be randomized, lowing chmod to set the SUID or SGID bit when
and failed fork() calls, changes to the system operating within such an environment. Addition-
time, and segmentation faults will all be logged. ally, applications that are running within such an
Enabling the Medium security level will also re- environment will not be allowed to insert loadable
strict total access to /proc to those who are in modules, perform raw I/O, configure network de-
the wheel group. This hides each user’s proc- vices, reboot the system, modify immutable files,
esses from other users and denies writing to or change the system’s time.
/dev/kmem, /dev/mem, and /dev/port.
Choosing this security level will also cause the
This makes it more difficult to patch kernel-based kernel’s stack to be laid out randomly, to prevent
root kits into the running kernel. Also, process kernel-based buffer overrun exploits from suc-
memory address space layouts are randomized, ceeding. In addition, the kernel’s symbols will be
making it harder for an attacker to successfully hidden – making it even more difficult for an in-
exploit buffer overrun attacks. Because of this, truder to install Trojan code into the running kernel
information on process address space layouts is - and filesystem mounting, remounting, and un-
removed from /proc as well. Because of these mounting will be logged.
/proc restrictions, you will need to run your
www.insecuremag.com 48
The High security level also enables grsecurity’s is defined. Unfortunately, GCC puts the trampoline
PaX code, which enables nonexecutable memory function’s code on the stack, so PaX will break
pages. Enabling this will cause many buffer over- any programs that rely on this. However, PaX can
run exploits to fail, since any code injected into the provide emulation for trampoline functions, which
stack through an overrun will be unable to exe- can be enabled on a per-program basis with
cute. However, it is still possible to exploit a pro- chpax, as well by using the -E switch.
gram with buffer overrun vulnerabilities, although
this is made much more difficult by grsecurity’s If you do not like the sets of features that are en-
address space layout randomization features. PaX abled with any of the predefined security levels,
can also carry with it some performance penalties you can just set the kernel option to “custom” and
on the x86 architecture, although they are said to enable only the features you need.
be minimal. In addition, some programs – such as
XFree86, wine, and Java virtual machines – will After you’ve set a security level or enabled the
expect that the memory addresses returned by specific options you want to use, just recompile
malloc() will be executable. Unfortunately, PaX your kernel and modules as you normally would.
breaks this behavior, so enabling it will cause You can do that with commands similar to these:
those programs and others that depend on it to
fail. Luckily, PaX can be disabled on a per- # make dep clean && make bzImage
program basis with the chpax utility # make modules && make
(chpax.grsecurity.net). modules_install
To disable PaX for a program, you can run a Then reboot with your new kernel. In addition to
command similar to this one: the kernel restrictions already in effect, you can
now use gradm to set up ACLs for your system.
# chpax -ps /usr/bin/java
As you can see, grsecurity is a complex but tre-
There are also other programs that make use of mendously useful modification of the Linux kernel.
special GCC features, such as trampoline func- For more detailed information on installing and
tions. This allows a programmer to define a small configuring the patches, consult the extensive
function within a function, so that the defined func- documentation at www.grsecurity.net/papers.php.
tion is only in the scope of the function in which it
Excerpted from “Network Security Hacks” by Andrew Lockhart, (ISBN: 0–596–00643–8). Copyright 2005,
O'Reilly Media, Inc. www.oreilly.com All rights reserved.
www.insecuremag.com 49
Please introduce yourself, your company blackmailing of proprietors, all of which can lead to
and your line of work. direct material losses.
My name is Sergey Ryzhikov and I am the Direc- What differentiates Bitrix Site Manager
tor of Bitrix (www.bitrixsoft.com). Today’s base line from other similar content management
of our company is the development of the Bitrix systems?
Site Manager software. The Bitrix Site Manager is
a content management solution (CMS) that en- It is a common practice to develop a stand-alone
ables users to effectively manage a corporate web CMS or an e-store without content management
site. We are technology partners with more than capabilities. Different Web-development compa-
400 Web-development companies in more than 30 nies produce stand-alone Web statistics analyz-
countries. ers, forums, and technical support systems. As a
result, these components offer different user pro-
Almost on a daily basis we are hit by in- files, different security policies, and different user
formation on new security vulnerabilities interfaces.
affecting popular web applications. In your
opinion, what are the current trends re- Not only is this inconvenient, but it prohibits
lated to security issues in web based ap- growth and development of Internet projects and
plications and what can be done to mini- increases the cost of implementation and owner-
ship. The result is obvious: companies cannot run
mize the threat?
their e-businesses effectively.
Today, attacks on Web-based businesses make
We create a package which includes everything
up more than 50 percent of all IT crimes. It’s obvi-
that a modern web site might require, and then
ous that company web sites will continue to be
some. Our software covers virtually every busi-
major targets for Internet criminals.
ness objective related to e-business. Today we
offer 19 modules that share a unified style of archi-
First of all, there are non-profit hacks targeting
tecture and a common user interface. This set of
web sites of large corporations and state institu-
modules satisfies the business-requirement needs
tions. Such hacks usually aim to produce self-
of 95% of all web sites.
advertisement and hit the company image. In ad-
dition to this, there are also a large number of
There is one serious advantage of our product that
commercial hacks. Cases like this are rarely dis-
I can’t pass over in silence. Any edition of the Bi-
covered right away, since the purpose of these
trix Site Manager allows for multiple sites to be
hacks is information theft.
built using a single product copy. These sites can
be managed, maintained, and analyzed in a cen-
Undoubtedly, hacks of corporate web sites affect
tralized fashion, using a common interface. As
both the image and reputation of these compa-
companies master the Internet, their sites grow
nies. When a hack becomes public knowledge,
and become more developed; this further implies
these incidents become extremely troublesome.
that it’s only sensible to use a single software
The greatest concern of these companies, how-
package to manage all of the sites.
ever, is the loss of sensitive information about the
organization and its clients, and the potential for
www.insecuremag.com 50
Your company launched a security section range of software products for monitoring the in-
of your web site, showing your current and formation environment security.
potential users that security is one of your
top priorities. What security mechanisms The vulnerability analysis was conducted using
and options does Bitrix Site Manager of- both the system source codes and a real web pro-
ject built upon the system. This has provided for
fer?
thorough “internal” and “external” testing, which
resulted in an exhaustive and trustworthy analysis.
Indeed, security issues are of utmost importance
to us and our clients. As you mentioned, we have
The audit results induced a range of updates.
launched on our site a special section solely de-
Right after the press conference, we have issued
voted to security issues. In this section, we have
an update which helped to strengthen all modules.
spotlighted common categories of vulnerabilities,
This significantly improved the administrative sec-
and explained how we have implemented systems
tions’ security against specific attacks – which I
within our product to protect the client’s security.
must say, were very exotic attacks. Furthermore,
none of the other existing Web solutions provide
While designing the Bitrix Site Manager architec- any protection against such attacks. Only a hand-
ture, we have placed special emphasis on ful of developers are informed of these, though
security-related problems. Allow me to list the ma- their risk and threat is very high. We have quickly
jor features which will enable Web developers to responded to the recommendations of the Positive
increase the security of their Web projects: Technologies company and implemented the nec-
essary means for protection.
• unified authorization system – all permissions
can be assigned to user groups only; As a result of the final audit stage, the Positive
• user profile is common for all modules; Technologies company has issued a certificate
• two-level system of access-level delimitation; entitled “The Secure Web Application”. As a matter
• an access-control system which is independent of fact, this is the first certificate of this kind issued
of the business logic; by the Positive Technologies company. I must add
• information can be encrypted during transmis- that we have signed a treaty to constantly monitor
sion; the security of updates. Finally, the Positive Tech-
• the SiteUpdate system; nologies company has made a decision to move
• independent journaling of executed pages in the their site to the Bitrix Site Manager. We consider
Statistics module; this decision to be an honor, coming from such a
• special policy of handling the volatile and exter- professional and experienced team as the Positive
nal data; Technologies company.
• double-checking of unsafe code portions.
Bitrix Site Manager uses SiteUpdate tech-
The methods by which we have implemented
nology which allows seamless upgrading
these features in our product, as well as the fea-
tures themselves, should indicate that our system possibilities. Automatic updates can be a
is secure. Nevertheless, we have engaged an in- security risk, how is this taken care of
dependent auditing company to verify this. Pres- within your software?
ently, all the updates that we publish are subjected
to an independent audit. The SiteUpdate security methods are paramount.
This technology provides for downloading and in-
Your software recently undergone an inde- stalling the latest product updates without having
pendent security audit. If any, what kind of to enlist the services of specially educated engi-
neers. This significantly improves the security of
potential security risks the auditors came
the site. By a simple button click, the client’s site
across? engine connects to our server via the license key
and provides the system updates that our client
We have called for engineers of the Positive Tech-
needs.
nologies company to conduct an independent se-
curity audit of the Bitrix Site Manager. Their task
To prevent downloading illegal updates, our clients
was to check the system architecture and how
may use the SSL certificate. This ensures that up-
well the security precautions are implemented.
dates will be downloaded encrypted from our
server only. But, as HTTPS requires special librar-
The Positive Technologies company carries out
ies to be installed on the client’s side, we have set
commercial “hacks” of Internet projects at the re-
the default transport mode for updates to HTTP.
source owner’s request. They also produce a
www.insecuremag.com 51
Some open source content management hosts large information content (for example, over
systems are (in)famous for their security 100.000 articles in on-line magazines).
problems. Are commercial content man-
agement systems more secure because Generally, Oracle based projects are more secure
there is money involved in the develop- and reliable, and can be easily scaled to serve un-
limited loads. Some of the clients simply make
ment and therefore this phase is done in a
Oracle their corporate standard and choose only
more professional way, or their main ad- the Oracle editions of the product.
vantage is that everyone can't poke around
their source code and hunt for vulnerabili- By the way, our clients can migrate from MySQL to
ties? Oracle in few hours by simply converting their da-
tabases while leaving the function and design of
Many open source content management systems the pages and applications untouched.
pay little attention to security. This can be the re-
sult of decentralized management and develop- What are the plans for the future product
ment of such systems, frequent change of devel- development?
opers, and the lack of unified security environment
architecture. Recently we have introduced a new module: "Ac-
tive Directory/LDAP Integrator", which provides
We consider security as one of the key factors in more simple and comfortable integration of the
product development. We invest much effort and client’s sites in their intranet and extranet networks
money into security analysis and constant audit. built upon Windows or UNIX/Novell. We have
launched a new redesigned beta version of the
If you would run a webserver for your Search module with support for English morphol-
company, would you use Linux or a Win- ogy. Search has become faster and more precise.
dows based system?
This year we plan to release a new version – 4.1.
Our product is developed with PHP using MySQL It will implement a new visual editor featuring Fire-
as a free database or Oracle as a commercial da- fox support and a full-featured visual editor for de-
tabase. sign templates. This will help to make the first
steps in mastering the Bitrix Site Manager easier.
The Bitrix Site Manager runs on any software plat-
form, such as UNIX, Linux, Sun, FreeBSD, HP-UX The new version will include a rich set of functions
and Windows. The Apache web server is mostly that provide support for selling digital content,
used, even on the Windows platform. Most of our manager of the client’s virtual accounts, and a new
clients install the system on Linux or FreeBSD. version of the e-store. This version will include up-
dates of the Statistics, Newsletter, Helpdesk, and
At the same time, many projects having a high at- other modules. Without a doubt, this new version
tendance are implemented on the Windows plat- will come under the banner of security! Version 4.1
form. In my opinion, this is due to the fact that the is not a full stop, but just a stage. We keep extend-
UNIX system is capable of serving heavier load ing the task list according to the dialogue with our
than the Windows systems, given similar hardware partners and clients.
resources. Traditionally, experienced administra-
tors install FreeBSD or Linux because they con- This year we plan to release the first .NET edition
sider these systems more secure and efficient. of the product in the “Standard” and “Web Analyt-
ics” editions. The new edition will be based on
In general, Oracle is used for large-scale projects conceptually different architecture, though. This
with heavy traffic (more than 50.000 unique visitor will allow our partners to offer their clients a com-
per day or 500.000 pages), or if the web resource plete range of solutions for all popular platforms
and databases.
www.insecuremag.com 52
Encryption can provide strong security for data at rest, but developing a
database encryption strategy must take many factors into consideration.
Encryption at the database level, versus application level and file level
has proved to be the ideal method to protect sensitive data and deliver
performance.
Organizations must balance between the require- offloading. Benchmarks in customer environments
ment for security and the desire for excellent per- demonstrated the criticality of making the right se-
formance. Building and maintaining a secure and lection between the different topologies for data-
efficient cryptographic engine is not the easiest base encryption implementations.
task. This is a specialized and complex solution
area and if internal resources don’t have the cryp- This article reviews the performance aspects of
tography expertise in relation to IT environment, three dominant topologies for database encryption
outside expertise should be used to ensure supe- and offers detailed guidance on scalable imple-
rior performance. mentations of data at rest encryption in an enter-
prise environment, including encryption, key man-
The best practice, in nearly all cases, is to use an agement, backup, auditing and logging should be
engine that’s already available and tested. Pack- deployed to optimize security, performance, scal-
aged database encryption solutions have proven ability, and administration.
to be the best alternative to protect sensitive data.
There is a multitude of techniques and alternative Introduction
topologies for encryption at the database level. In
real-world scenarios, are complex issues and ex- Building and maintaining a secure and efficient
perts should be used who understand all available cryptographic engine is not the easiest task. The
options and the impact for each particular cus- best practice, in nearly all cases, is to use an en-
tomer environment. Encryption engines and serv- gine that’s already available and tested. In a
ices come in three flavors: central, local and dedi- straight comparison of costs, Local Encryption
cated. In a straight comparison of costs, Local En- Services are generally cheaper but not secure.
cryption Services are generally cheaper but not Dedicated Encryption Services provides high
secure. Dedicated Encryption Services provides availability with key caching and real cpu offload-
high availability with key caching and real cpu ing.
www.insecuremag.com 53
Benchmarks in customer environments demon- compromise is a combination of physical security
strated the criticality of making the right selection and key management technology, including strin-
between the different topologies for database en- gent security standards throughout the private key
cryption implementations. A central topology lifecycle.
benchmarked decryption of only a few hundred
database rows per second and a more distributed Data at rest encryption – different ap-
hybrid topology benchmarked in the range of mil- proaches have its advantages and disad-
lion rows per second, typically needed in environ- vantages
ments with a high volume OLTP or parallel sys-
tems for decision support. Be aware that exposing There are many architectures, techniques, and
encryption services as a network resource will in- tools available to Security and IT organizations to
troduce an additional point of attack, and very lim- ensure security and performance are balanced
ited scalability in a database environment. Private and optimized. Each of these approaches has its
keys should be stored encrypted with several AES advantages and disadvantages. Database security
encryption keys that are nested within a hierarchy is a wide research area and includes topics such
in which each key is protected by a parent key. as statistical database security, intrusion detection,
This multi-layer hierarchy of keys ensures the and most recently privacy preserving data mining.
highest level of protection against attack. Engines In this work we have addressed and evaluated the
come in three flavors: central, local and dedicated. most critical issue for the success of encryption in
Not protected properly, stored unprotected in a databases, performance. To achieve that, we have
software environment, and unprotected in server analysed different solution alternatives. Each to-
memory, keys are vulnerable to discovery. What ís pology effects security and performance differently
needed? The best protection against private key and has advantages and disadvantages.
THE BEST PROTECTION AGAINST PRIVATE KEY COMPROMISE IS A COMBINATION OF
PHYSICAL SECURITY AND KEY MANAGEMENT TECHNOLOGY, INCLUDING STRINGENT
SECURITY STANDARDS THROUGHOUT THE PRIVATE KEY LIFECYCLE
Issues with application level encryption - One is the granularity of data to be encrypted or
and storage level encryption decrypted. The field, the row and the page, typi-
cally 4KB, are the alternatives. The field is the best
Application-layer encryption requires rewrite of choice, because it would minimize the number of
existing applications that is impractical due to lim- bytes encrypted. However, as we have discov-
ited IT resources, lack of access to source code, ered, this will require methods of embedding en-
or a lack familiarity with old code. Rewriting appli- cryption within relational databases or database
cations is also very costly, risky and introduces an servers.
implementation time delay factor. Lastly, all appli-
cations that access the encrypted data must also - The second dimension is software versus hard-
be changed to support the encryption/decryption ware level implementation of encryption algo-
model. Storage-layer encryption alone can only rithms. Our results show that the choice makes
protect against a narrow range of threats, namely significant impact on the performance. We have
media theft and storage system attacks. discovered encryption within relational databases
based on hardware level implementation of en-
Database-layer encryption cryption algorithms entail a significant start up cost
for an encryption operation. Each model also of-
Database-layer encryption protects the data within fers different operational performance, tuning pos-
the DBMS and also protects against a wide range sibilities, and encryption offloading capabilities.
of threats, including storage media theft, well The loss of granular protection will impact the se-
known storage attacks, database-layer attacks, curity level.
and malicious DBAs. Deployment at the column
level within a database table, coupled with access - The third dimension is the location of the encryp-
controls will prevent theft of critical data. tion service – local service, remote procedure
service, or network attached service. Choosing the
Different dimensions of database encryp- point of implementation not only dictates the work
tion support that needs to be done from an integration per-
spective but also significantly affects the overall
There are three main dimensions to encryption security model.
support in databases:
www.insecuremag.com 54
Not always practical to encrypt data as characteristics of applications to the data that is
soon as it enters the network encrypted. While this solution can certainly secure
data, it does require some integration work at the
The sooner the encryption of data occurs, the database level, including modifications of existing
more secure the environment however, due to dis- database schemas and the use of triggers and
tributed business logic in application and database stored procedures to undertake encrypt and de-
environments, it is not always practical to encrypt crypt functions.
data as soon as it enters the network. Encryption
performed by the DBMS can protect data at rest, Performance aspects of database-level en-
but you must decide if you also require protection cryption
for data while it's moving between the applications
and the database. We considered several possible Additionally, careful consideration has to be given
combinations of different encryption approaches, to the performance impact of implementing a da-
namely; software and hardware level encryption, tabase encryption solution, particularly if support
and different data granularity. We started with for accelerated index-search on encrypted data is
software encryption at field level. We then devel- not used. First, enterprises must adopt an ap-
oped search acceleration support to index en- proach to encrypting only sensitive fields. Second,
crypted fields, and experienced a low performance this level of encryption must consider leveraging
overhead when searching on encrypted fields, in- hardware to increase the level of security and po-
cluding primary index fields. We finally directed tentially to offload the cryptographic process in
our research and experiments to hardware level order to minimize any performance impact. The
encryption use only for master key encryption. primary vulnerability of this type of encryption is
that it does not protect against application-level
Algorithm performance and security attacks as the encryption function is strictly imple-
mented within the DBMS. If we compare the re-
Initially we considered several encryption algo- sponse time for a query on unencrypted data with
rithms AES, RSA and Blowfish for the implementa- the response time for the same query over the
tion. We conducted experiments using these algo- same data, but with some or all of it encrypted, the
rithms and found that the performance and secu- response time over encrypted data will increase
rity of the AES algorithm is better than the RSA due to both the cost of decryption as well as rou-
implementation and the Blowfish algorithm imple- tine and/or hardware invocations. This increase is
mentation. AES is fast, compared to other well- referred to as the encryption penalty. An observa-
known encryption algorithms such as DES. DES is tion according to recent studies is that, different
a 64-bit block cipher, which means that data is en- fields have different sensitivity. It is possible for
crypted and decrypted in 64-bit chunks. This has Hybrid to support encryption only on selected
implication on short data. Even 8-bit data, when fields of selected tables.
encrypted by the algorithm will result in 64 bits.
Encryption, by its nature, will slow down most SQL
Optimizing database-level encryption im- statements. If some care and discretion are used,
plementations the amount of extra overhead should be minimal.
Also, encrypted data will have a significant impact
Database-level encryption allows enterprises to on your database design. In general, you want to
secure data as it is written to and read from a da- encrypt a few very sensitive data elements in a
tabase. This type of deployment is typically done schema, like Social security numbers, credit card
at the column level within a database table and, if numbers, patient names, etc. Some data values
coupled with database security and access con- are not very good candidates for encryption — for
trols, can prevent theft of critical data. Database- example booleans (true and false), or other small
level encryption protects the data within the DBMS sets like the integers 1 through 10. These values
and also protects against a wide range of threats, along with a column name may be easy to guess,
including storage media theft, well known storage so you want to decide whether encryption is really
attacks, database-level attacks, and malicious useful. Creating indexes on encrypted data is a
DBAs. Database-level encryption eliminates all good idea in some cases. Exact matches and
application changes required in the application- joins of encrypted data will use the indexes you
level model, and also addresses a growing trend create. Since encrypted data is essentially binary
towards embedding business logic within a DBMS data, range checking of encrypted data would re-
through the use of stored procedures and triggers. quire table scans. Range checking will require de-
Since the encryption/decryption only occurs within crypting all the row values for a column, so it
the database, this solution does not require an en- should be avoided if not tuned appropriately with
terprise to understand or discover the access an accelerated search index.
www.insecuremag.com 55
Central, local or dedicated encryption serv- ized solutions for each application and data stor-
ices age system. Applications and databases would not
be impacted by an application specific implemen-
The cryptographic engine lies at the core of the tation. This would alleviate the problem of main-
infrastructure. It implements algorithms, such as taining the software and administrating privacy for
AES, DES, RSA, SHA, upon which the rest of the each specific application and database.
system depends. Any request to encrypt, decrypt,
hash, or sign data ultimately passes through the Local encryption services
engine. The management of encryption keys are
the foundation of all encryption-based security so- A Local Encryption Service is one in which the
lutions. Each of these approaches has its advan- cryptography occurs on the same cpu as the rest
tages and disadvantages. Database security is a of the application ís processing. Typically for a Lo-
wide research area and includes topics such as cal Encryption Service, the algorithms are in-
statistical database security, intrusion detection, cluded as part of the application or as a library to
and most recently privacy preserving data mining. which the application is linked. Examples of Local
Users wishing to access data will now securely Encryption Services include RSA's Crypto-J, Cryp-
access it using the privacy management infra tix, Mcrypt, and encryption libraries and toolkits
structure instead of developing multiple custom- included in products from some database vendors.
Local encryption services are generally be balanced against security and performance is-
cheaper but not secure sues.
A Local Encryption Service is often easier to im- Dedicated encryption services
plement as there is no need to configure a sepa-
rate hardware interface, and since there is no Dedicated Encryption Services contain separate
special hardware or software to purchase, the Lo- processes dedicated just to cryptography. Dedi-
cal Encryption Service can be significantly less cated Encryption Services could also contain a set
expensive, even free. Of course, the keys used by of separated cpu's dedicated just to cryptography.
the engine are also significantly less secure. The A typical example of a Dedicated Encryption Serv-
application's performance will also suffer to a great ice is Protegrity Secure.Data Server in which the
extent by the inclusion of cryptographic processing cryptographic processes are mounted. Another
on the application's cpu, and potential require- example of a Dedicated Encryption Service is a
ments in searching of encrypted database col- Hardware Security Module (hsm) in which the
umns. Compared to a Dedicated Encryption Serv- cryptographic cpu is mounted within a standalone,
ice, a Local Encryption Service offers a reduction typically tamper-resistant, enclosure. An hsm
in complexity in some areas. A Dedicated Encryp- might communicate with the application through a
tion Service requires the installation and configu- pci card, scsi, or over ipc (inter process communi-
ration of a separate layer of hardware. Local En- cation). The Central Encryption Services may con-
cryption Services avoid this. However, Dedicated tain a number of separate cpu's dedicated just to
Encryption Services typically store the key away cryptography. To maintain a high level of security
from the data and application and then wrap the the server platform should only contain securely
key in layers of encryption and optionally use encrypted lower level data encryption keys. Key
tamper-resistant hardware. encryption master keys should always be stored
separately outside the server platform. Private
Approximating this level of security using a Local keys should be stored encrypted with several AES
Encryption Service requires a comprehensive and encryption keys that are nested within a hierarchy
mature implementation. In a straight comparison in which each key is protected by a parent key.
of costs, Local Encryption Services are generally This multi-layer hierarchy of keys ensures the
cheaper but not secure. The cost savings need to highest level of protection against attack.
www.insecuremag.com 56
Central encryption services The Network Attached Encryption Device
(NAED)
Central Encryption Services can be implemented
as a remote server with an optional HSM, or a The Network Attached Encryption (NAED) is im-
network appliance (NAED). A typical example of a plemented as a Network Attached Encryption Ap-
Central Encryption Service is a Server with a pliance that scales with the number of Network
Hardware Security Module (hsm) in which the Attached Encryption Appliances available. A
cryptographic cpu is mounted within a standalone, NAED is a hardware device that resides on the
typically tamper-resistant, enclosure. An hsm network, houses the encryption keys and executes
might communicate with the application over the all crypto operations. This topology has the added
local area network using ssl. The goal of an hsm is security of physically separating the keys from the
to provide a secure environment for keys thus data. However, this added security comes with a
most hsms combine the functionality of a key vault heavy price; performance can be 10–100 times
and engine. worse than alternative methods. The benchmarks
showed a throughput of between 440 and 1,100
Relying only on remote central encryption support row-decryptions per second. In prior work with IBM
is not satisfactory, since it would always penalize Research we addressed some critical perform-
network and total system performance, and more ance issues when using HSM support. A coming
importantly, it is likely to open new security holes paper will address the security exposure with API
in the form of attacks on network exposed encryp- level attacks when using HSM support, including
tion services. Network Attached Encryption Appliances.
A NAED IS A HARDWARE DEVICE THAT RESIDES ON THE NETWORK, HOUSES THE EN-
CRYPTION KEYS AND EXECUTES ALL CRYPTO OPERATIONS
Encryption as a network resource – a new Interface to encryption hardware add over-
point of attack head
Be aware that exposing encryption services as a Central/Dedicated Encryption Services may be
network resource will introduce an additional point used in environments where performance and
of attack. An integrated central and distributed so- scalability are not critical requirements. A Dedi-
lution can protect from this vulnerability. Also, look cated Encryption Service is typically a specially
for industry standard api support. Adopting a stan- constructed device which is connected via a cable
dard such as pkcs#11, will help ease the transition to the computer needing cryptographic services,
from one vendor's engine to another, and in some including pci or scsi, for directly connected en-
cases between different engines from the same gines, or ethernet for network connected encryp-
vendor. tion services. When selecting a Dedicated Encryp-
tion Service, consider performance, scalability,
Denial of Service attacks and availability. Most Dedicated Encryption Serv-
ices will perform cryptographic operations faster
A network attached engine, on the other hand, than Local Encryption Services for larger blocks of
does not provide high availability, unless multiple data, however the interface to the hardware can
engines are configured into a high availability clus- add considerable overhead for shorter blocks of
ter. Denial of Service attacks are another related data. This overhead may be noticeable on directly
concern with network attached engines. Since the connected engines at higher transaction volumes.
engine is available over tcp/ip, an attacker could Network based engines, though, might carry a
flood the engine with traffic and block legitimate performance penalty from the need to negotiate a
cryptographic requests. If required information secure tcp connection. If the connection remains
can't be decrypted, then a customer may not be open between requests, then the overhead may
able to place an order or access account informa- be lower but it certainly should be tested.
tion. If the database stored encrypted records that
are critical for the business operation, then a suc- The myth that NAEDS off-load work from
cessful denial of service attack could be severe. the database
None of the above are reasons not to use Dedi-
cated Encryption Services, but rather factors to This example debunks a well-publicized myth, that
keep in mind when selecting a Dedicated Encryp- NAEDs off-load work from the database. There
tion Service. isn't an off-load of work since this solution must
perform one encryption operation in the database,
www.insecuremag.com 57
which is the same for other topologies, in addition A mature hybrid solution
to the encryption functions at the NAED.
A powerful Hybrid solution combines the benefits
There are three points of overhead with of a Central Encryption Service with a Dedicated
this topology Encryption Service, on a general purpose com-
puters running a standard operating system, but
Let's explore a simple example to demonstrate the stripped of all but the most essential services.
overhead; a user requests 500,000 rows of en- Amongst those services would be a cryptographic
crypted data. server and a key storage module. To maintain a
high level of security the server platform should
When a user requests secured data, the security only contain securely encrypted lower level data
system manages the process of retrieving en- encryption keys. Key encryption master keys
crypted data from the database, ensuring that the should always be stored separately outside the
request is from an authorized user, and performing server platform on the central encryption services
the decryption process. platform. Private keys should be stored encrypted
with several AES encryption keys that are nested.
In this topology, the encryption agent handles the
request and retrieves the encrypted data from the The Hybrid solution Central Encryption Services
database. It sends the encrypted data over the provides secure and flexible key management and
network to be decrypted by the NAED. key backup. Dedicated Encryption Services pro-
vides high availability with key caching and real
Inside the NAED are the keys and the algorithms cpu offloading. Packaged and Integrated Local
to decrypt the data. However once decrypted, we Encryption Services operations provides the high-
have clear-text information that needs to be sent est operational performance and the highest
back over the wire to the database server. This availability for encryption services.
requires that we re-secure the information for
transit, typically through a secure communication All data items and keys are not equal
process such as SSL. When the data arrives at
the agent on the database server, it has to be re- Some data requires a higher level of protection.
turned to clear-text, and then it is served up to the Data classification can be used to determine if a
calling application. specific data item should be processed locally, in a
dedicated service, central service, or on a hsm.
1. A NAED topology has three points of encryption Risk management can help in defining the balance
versus one for other methods. In the example between these requirement for security, cost, and
above, the 500,000 rows of data are sent over the acceptable performance and scalability.
wire to be decrypted at the NAED. The clear text is
then encrypted using SSL to send back over the Some encryption keys requires a higher level of
network and decrypted at the database to be protection. Master keys and some data encryption
served in clear text to the application. keys requires a higher level of protection. Data
classification can be used to determine if a spe-
2. Network overhead is caused by sending all cific data item encryption key should be processed
500,000 rows over the network to be decrypted by locally, in a dedicated service, central service, or
the NAED and then must return over the network on a hsm. Risk management can help in defining
to the database. the balance between these requirements for secu-
rity, cost, and acceptable performance and scal-
3. The NAED is a stateless device and needs to ability.
be initialised/set-up before each row is decrypted.
In this simple example, the NAED is set-up A high level of security
500,000 times. The set-up has a large overhead.
To maintain a high level of security the server plat-
The Network Attached Encryption Device (NAED) form should only contain securely encrypted lower
topology has proven in tests, due to the three level data encryption keys. Key encryption master
points of overhead, to perform by an order of keys should always be stored separately outside
magnitude, worse than alternative structures. the server platform on the central encryption serv-
Each round trip over the network is roughly 1 milli- ices platform. While most Dedicated Encryption
second per row. In the example above this would Services are devices specifically constructed for
be 500,000 x 1ms = 500 seconds compared to 1- cryptography, some Dedicated Encryption Serv-
25 seconds with alternative topologies. ices might be general purpose computers running
standard OSes, but stripped of all but the most
www.insecuremag.com 58
essential services. Amongst those services would automatically rotated based on the sensitivity of
be a cryptographic server and a key storage mod- the protected data. Dedicated Encryption Services
ule. At the heart of the server is a library such as are also vulnerable to memory attacks. However,
the ones used for a Local Encryption Service. For a well made Dedicated Encryption Service runs
that reason, these types of Dedicated Encryption only the minimal number of services. Since web
Services. Private keys should be stored encrypted servers, application servers, and databases have
with several AES encryption keys that are nested no place on a dedicated cryptographic engine,
within a hierarchy in which each key is protected these common attack points aren't a threat. This
by a parent key. This multi-layer hierarchy of keys severely constrained attack surface makes it much
ensures the highest level of protection against at- more difficult to gain the access needed to launch
tack. a memory attack. To maintain a high level of secu-
rity backups contain the encrypted data and only
Effective key protection in memory securely encrypted lower level keys. Master keys
should be backed up separately.
Memory attacks may be theoretical, but crypto-
graphic keys, unlike most other data in a computer Secure key back up
memory, are random. Looking through memory
structures for random data is very likely to reveal A weak link in the security of many networks is the
key material. Well made libraries for use as Local backup process. Often, private keys and certifi-
Encryption Services go to great efforts to protect cates are archived unprotected along with configu-
keys even in memory. Key-encryption keys are ration data from the backend servers. The backup
used to encrypt the key while it is in memory and key file may be stored in clear text or protected
then the encrypted key is split into several parts only by an administrative password. This pass-
and spread throughout the memory space. Decoy word is often chosen poorly and/or shared be-
structures might be created that look like valid key tween operators. To take advantage of this weak
material. Memory holding the key is quickly zeroed protection mechanism, hackers can simply launch
as soon as the cryptographic operation is finished. a dictionary attack (a series of educated guesses
These techniques reduce the risk of memory at- based on dictionary words) to obtain private keys
tacks. Separate encryption can also be used for and associated certificates.
different data. These encryption keys can be
A WEAK LINK IN THE SECURITY OF MANY NETWORKS IS THE BACKUP PROCESS
High performance and scalability the number of processors and database server
available. In the Software topology the database
This topology combines the enhanced perform- server becomes the platform for encryption serv-
ance of the Software structure with the added se- ices, removing the network and a remote device
curity of a hardware device. A HSM, in some situa- from the equation.
tions, is an ideal way to add additional protection
for the most important element of any encryption Benchmarks from real world customer en-
solution ñ the encryption keys. HSM devices are vironments
fast and tamper proof, so they make an excellent
vault to store the crown jewels ñ the encryption We studied the industry standard SQL benchmark
keys. The performance in this topology is essen- as a model for workloads. Some simple sample
tially identical to the earlier pure software struc- tests on Oracle and DB2. The first benchmark was
ture, with an occasional transit to the HSM to re- focus on a particular customer scenario. Subse-
fresh and retrieve the master encryption keys. quent benchmarks used a workload combined
During the majority of processing time, perform- from multiple customer case studies. The techno-
ance is identical to the software solution. logical aspects of developing database privacy as
an enterprise IT infrastructure component lead to
In our 500,000-row example, in contrast to the new research challenges. First and fore-most is
NAED structure – where all 500,000 rows flowed the issue of encryption key management. Most
over the wire to the NAED – the encryption service corporations view their data as a very valuable
in the database server accesses the key from the asset. The key management system would need
HSM one time and thereafter all crypto operations to provide sufficient security measures to guard
are completed in the database by the software en- the distributed use of encryption keys. We propose
cryption service. The Hybrid system is imple- a combined hardware and software based data
mented as distributed processes that scales with encryption system as the solution to this problem.
www.insecuremag.com 59
A distributed policy and audit capability is pro- servers should provide cryptographic availability.
posed for the control the use of different encryp- Should one engine fail, then processing could shift
tion keys. Detailed investigation of this solution is to the other servers where the engines were still
presented below. Since the interaction between operational.
the database and the enterprise IT infrastructure
component there are potential over-heads intro- Conclusion
duced by encryption. Therefore the sources of per-
formance degradation and its significance should We addressed performance as a particularly vital
be determined. problem and evaluated different solutions for da-
tabase encryption.
How to off-load encryption and scale with
additional servers In this article, we discussed the Hybrid, a data-
base privacy solution built on top of all major rela-
As mentioned before, cryptography consumes a tional databases.
fair amount of cpu cycles; with a Local Encryption
Service application performance could be spread The Hybrid model introduces many significant
over a number of local processors. Dedicated En- challenges primary of which are the additional
cryption Services off-load the encryption to a pool overhead of searching on encrypted data an infra-
of separate processors. structure to guarantee data privacy, and manage-
ment of such an enterprise IT infrastructure com-
Some Dedicated Encryption Services also use ponent. We have addressed these issues.
special proprietary processors. Similar perform-
ance out of general purpose hardware could be Our experiments using several benchmarks
easy and less expensive when using state of the showed that the overhead is tolerable when using
art general servers. suitable encryption architecture. The Hybrid model
implements a scalable approach for data privacy
Obtaining a relevant degree of key security with a and security in which a security administrator pro-
Local Encryption Service will require key storage tecting privacy at the level of individual fields and
separated from the local server. A central server records, and providing seamless mechanisms to
with optional hardware to store the key can pro- create, store, and securely access databases.
vide a cost effective solution in some environ- Such a model alleviates the need for organizations
ments. to purchase expensive hardware, deal with soft-
ware modifications, and hire professionals for en-
A final security consideration with Local Encryption cryption key management development tasks.
Services is due to fact that the same physical
memory is shared between the Local Encryption We proposed, implemented, and evaluated differ-
Service and the application. Many modern appli- ent encryption schemes. We showed the drastic
cation architectures scale by adding additional decrease in query execution times from distributed
servers. In the case of directly connected engines, software level encryption. We showed that the Hy-
each new server requires a new engine. Directly brid database encryption solution is the most suc-
connected engines in a highly available cluster of cessful offering for most application environments.
Ulf T. Mattsson is the CTO of Protegrity. His extensive IT and security industry experience includes 20 years
with IBM as a manager of software development and a consulting resource to IBM's Research and Develop-
ment organization, in the areas of IT Architecture and IT Security.
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We have attended this year’s RSA Conference Europe, held near Prater entertainment center in Austrian capi-
tal Vienna. If you are not familiar with the concept of this conference, it focuses on providing quality class ses-
sions on all the major aspects of information security. Our coverage is available at:
www.net-security.org/article.php?id=849
Besides these sessions, the most visited presentations included Keynotes by Scott Charney, VP Trustworthy
Computing at Microsoft, Art Coviello, RSA Security CEO and ex Director General of MI5 Stella Rimington. The
exibition area of this years’ event was the biggest one we have seen since our first RSA Conference Europe
back in 2002. It was announced that the 2006 conference will be held in Nice, France.
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